Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Más filtros

Bases de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Am J Physiol Lung Cell Mol Physiol ; 320(5): L688-L704, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33502939

RESUMEN

Early therapeutic effect of intratracheally (IT)-administered extracellular vesicles secreted by mesenchymal stem cells (MSC-EVs) has been demonstrated in a rat model of bronchopulmonary dysplasia (BPD) involving hyperoxia exposure in the first 2 postnatal weeks. The aim of this study was to evaluate the protective effects of IT-administered MSC-EVs in the long term. EVs were produced from MSCs following GMP standards. At birth, rats were distributed in three groups: (a) animals raised in ambient air for 6 weeks (n = 10); and animals exposed to 60% hyperoxia for 2 weeks and to room air for additional 4 weeks and treated with (b) IT-administered saline solution (n = 10), or (c) MSC-EVs (n = 10) on postnatal days 3, 7, 10, and 21. Hyperoxia exposure produced significant decreases in total number of alveoli, total surface area of alveolar air spaces, and proliferation index, together with increases in mean alveolar volume, mean linear intercept and fibrosis percentage; all these morphometric changes were prevented by MSC-EVs treatment. The medial thickness index for <100 µm vessels was higher for hyperoxia-exposed/sham-treated than for normoxia-exposed rats; MSC-EV treatment significantly reduced this index. There were no significant differences in interstitial/alveolar and perivascular F4/8-positive and CD86-positive macrophages. Conversely, hyperoxia exposure reduced CD163-positive macrophages both in interstitial/alveolar and perivascular populations and MSC-EV prevented these hyperoxia-induced reductions. These findings further support that IT-administered EVs could be an effective approach to prevent/treat BPD, ameliorating the impaired alveolarization and pulmonary artery remodeling also in a long-term model. M2 macrophage polarization could play a role through anti-inflammatory and proliferative mechanisms.


Asunto(s)
Displasia Broncopulmonar/complicaciones , Modelos Animales de Enfermedad , Vesículas Extracelulares/fisiología , Lesión Pulmonar/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Administración por Inhalación , Animales , Animales Recién Nacidos , Femenino , Hiperoxia/fisiopatología , Lesión Pulmonar/etiología , Lesión Pulmonar/patología , Masculino , Alveolos Pulmonares/citología , Alveolos Pulmonares/metabolismo , Arteria Pulmonar/citología , Arteria Pulmonar/metabolismo , Ratas , Ratas Sprague-Dawley , Tráquea
2.
Am J Physiol Lung Cell Mol Physiol ; 316(1): L6-L19, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30284924

RESUMEN

Mesenchymal stem cells (MSCs) prevent the onset of bronchopulmonary dysplasia (BPD) in animal models, an effect that seems to be mediated by their secreted extracellular vesicles (EVs). The aim of this study was to compare the protective effects of intratracheally (IT) administered MSCs versus MSC-EVs in a hyperoxia-induced rat model of BPD. At birth, rats were distributed as follows: animals raised in ambient air for 2 wk ( n = 10), and animals exposed to 60% oxygen for 2 wk and treated with IT-administered physiological solution ( n = 10), MSCs ( n = 10), or MSC-EVs ( n = 10) on postnatal days 3, 7, and 10. The sham-treated hyperoxia-exposed animals showed reductions in total surface area of alveolar air spaces, and total number of alveoli ( Nalv), and an increased mean alveolar volume (Valv). EVs prompted a significant increase in Nalv ( P < 0.01) and a significant decrease in Valv ( P < 0.05) compared with sham-treated animals, whereas MSCs only significantly improved Nalv ( P < 0.05). Small pulmonary vessels of the sham-treated hyperoxia-exposed rats also showed an increase in medial thickness, which only EVs succeeded in preventing significantly ( P < 0.05). In conclusion, both EVs and MSCs reduce hyperoxia-induced damage, with EVs obtaining better results in terms of alveolarization and lung vascularization parameters. This suggests that IT-administered EVs could be an effective approach to BPD treatment.


Asunto(s)
Displasia Broncopulmonar/terapia , Vesículas Extracelulares/trasplante , Células Madre Mesenquimatosas/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
3.
Exp Lung Res ; 44(4-5): 226-240, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30198795

RESUMEN

AIM OF THE STUDY: The lung architecture of newborns appears to be affected by an inflammatory reaction to maternal choriodecidual layer infection. L-citrulline (L-Cit) was administered to pregnant rats exposed to intra-amniotic lipopolysaccharide (LPS)-induced chorioamnionitis to investigate its effect on neonatal lung injury. MATERIALS AND METHODS: The pups were assigned to four experimental groups: 1- pups exposed to intra-amniotic NaCl but not to postnatal L-Cit (Controls); 2 - pups exposed to intra-amniotic NaCl as well as to postnatal L-Cit treatment (L-Cit group); 3 - pups exposed to prenatal LPS but not to postnatal (LPS); 4- pups exposed to prenatal LPS as well as to postnatal L-Cit treatment (LPS + L-Cit). Some pups in each group were sacrificed on postnatal (P) day 3 and others on day 7. The pups' lungs were harvested for morphometric analysis; cytokine, arginase 1, and VEGF values were quantified. Serum arginine, citrulline, asymmetric dimethylarginine (ADMA), symmetric dimethylarginine, NG-monomethyl arginine, and homoarginine levels were determined using UPLC-MS/MS. RESULTS: L-Cit attenuated the disruption of alveolar growth in the LPS + L-Cit group. Arginine, homo-arginine, and ADMA levels fell in the LPS treated groups. Arginine and ADMA rose at P7 in the L-Cit group whose members also showed higher VEGF levels with respect to the Controls. The Controls, instead, showed higher IL-10 and IL-1ß values with respect to the L-Cit group at P7. Arginase 1 was higher in the LPS groups with respect to the Controls at P7. CONCLUSIONS: L-Cit improved alveolar and vascular growth diminishing the lung inflammatory response in the newborn rats exposed to intra-amniotic LPS. The ADMA/DDAH/NO pathway appeared to counteract proinflammatory cytokine production and to sustain macrophage migration.


Asunto(s)
Corioamnionitis/tratamiento farmacológico , Citrulina/farmacología , Lesión Pulmonar/tratamiento farmacológico , Animales , Animales Recién Nacidos , Arginina/análogos & derivados , Arginina/metabolismo , Vasos Sanguíneos/crecimiento & desarrollo , Corioamnionitis/inducido químicamente , Corioamnionitis/patología , Citrulina/uso terapéutico , Citocinas/biosíntesis , Citocinas/metabolismo , Femenino , Lipopolisacáridos/farmacología , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/patología , Macrófagos Alveolares/citología , Óxido Nítrico/metabolismo , Embarazo , Alveolos Pulmonares/crecimiento & desarrollo , Ratas
4.
Int J Mol Sci ; 19(5)2018 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-29710813

RESUMEN

Skeletal muscle tissue engineering (TE) aims to efficiently repair large congenital and acquired defects. Biological acellular scaffolds are considered a good tool for TE, as decellularization allows structural preservation of tissue extracellular matrix (ECM) and conservation of its unique cytokine reservoir and the ability to support angiogenesis, cell viability, and proliferation. This represents a major advantage compared to synthetic scaffolds, which can acquire these features only after modification and show limited biocompatibility. In this work, we describe the ability of a skeletal muscle acellular scaffold to promote vascularization both ex vivo and in vivo. Specifically, chicken chorioallantoic membrane assay and protein array confirmed the presence of pro-angiogenic molecules in the decellularized tissue such as HGF, VEGF, and SDF-1α. The acellular muscle was implanted in BL6/J mice both subcutaneously and ortotopically. In the first condition, the ECM-derived scaffold appeared vascularized 7 days post-implantation. When the decellularized diaphragm was ortotopically applied, newly formed blood vessels containing CD31⁺, αSMA⁺, and vWF⁺ cells were visible inside the scaffold. Systemic injection of Evans Blue proved function and perfusion of the new vessels, underlying a tissue-regenerative activation. On the contrary, the implantation of a synthetic matrix made of polytetrafluoroethylene used as control was only surrounded by vWF⁺ cells, with no cell migration inside the scaffold and clear foreign body reaction (giant cells were visible). The molecular profile and the analysis of macrophages confirmed the tendency of the synthetic scaffold to enhance inflammation instead of regeneration. In conclusion, we identified the angiogenic potential of a skeletal muscle-derived acellular scaffold and the pro-regenerative environment activated in vivo, showing clear evidence that the decellularized diaphragm is a suitable candidate for skeletal muscle tissue engineering and regeneration.


Asunto(s)
Diafragma/química , Espacio Extracelular/química , Neovascularización Fisiológica , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Células Cultivadas , Quimiocina CXCL12/análisis , Quimiocina CXCL12/farmacología , Embrión de Pollo , Diafragma/citología , Femenino , Factor de Crecimiento de Hepatocito/análisis , Factor de Crecimiento de Hepatocito/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Factor A de Crecimiento Endotelial Vascular/análisis , Factor A de Crecimiento Endotelial Vascular/farmacología
5.
Int J Mol Sci ; 19(4)2018 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-29662006

RESUMEN

Hyperinsulinemia could have a role in the growing incidence of esophageal adenocarcinoma (EAC) and its pre-cancerous lesion, Barrett's Esophagus, a possible consequence of Gastro-Esophageal Reflux Disease. Obesity is known to mediate esophageal carcinogenesis through different mechanisms including insulin-resistance leading to hyperinsulinemia, which may mediate cancer progression via the insulin/insulin-like growth factor axis. We used the hyperinsulinemic non-obese FVB/N (Friend leukemia virus B strain) MKR (muscle (M)-IGF1R-lysine (K)-arginine (R) mouse model to evaluate the exclusive role of hyperinsulinemia in the pathogenesis of EAC related to duodeno-esophageal reflux. FVB/N wild-type (WT) and MKR mice underwent jejunum-esophageal anastomosis side-to end with the exclusion of the stomach. Thirty weeks after surgery, the esophagus was processed for histological, immunological and insulin/Insulin-like growth factor 1 (IGF1) signal transduction analyses. Most of the WT mice (63.1%) developed dysplasia, whereas most of the MKR mice (74.3%) developed squamous cell and adenosquamous carcinomas, both expressing Human Epidermal growth factor receptor 2 (HER2). Hyperinsulinemia significantly increased esophageal cancer incidence in the presence of duodenal-reflux. Insulin receptor (IR) and IGF1 receptor (IGF1R) were overexpressed in the hyperinsulinemic condition. IGF1R, through ERK1/2 mitogenic pattern activation, seems to be involved in cancer onset. Hyperinsulinemia-induced IGF1R and HER2 up-regulation could also increase the possibility of forming of IGF1R/HER2 heterodimers to support cell growth/proliferation/progression in esophageal carcinogenesis.


Asunto(s)
Reflujo Duodenogástrico/complicaciones , Neoplasias Esofágicas/etiología , Esófago/patología , Hiperinsulinismo/complicaciones , Animales , Modelos Animales de Enfermedad , Reflujo Duodenogástrico/metabolismo , Reflujo Duodenogástrico/patología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Esófago/metabolismo , Femenino , Hiperinsulinismo/metabolismo , Hiperinsulinismo/patología , Insulina/análisis , Insulina/metabolismo , Masculino , Ratones , Receptor ErbB-2/análisis , Receptor ErbB-2/metabolismo , Transducción de Señal
6.
Am J Physiol Lung Cell Mol Physiol ; 310(7): L680-8, 2016 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-26851258

RESUMEN

No papers are available about potentiality of fractal analysis in quantitative assessment of alveolarization in bronchopulmonary dysplasia (BPD). Thus, we here performed a comparative analysis between fractal [fractal dimension (D) and lacunarity] and stereological [mean linear intercept (Lm), total volume of alveolar air spaces, total number of alveoli, mean alveolar volume, total volume and surface area of alveolar septa, and mean alveolar septal thickness] parameters in experimental hyperoxia-induced models of BPD. At birth, rats were distributed between the following groups: 1) rats raised in ambient air for 2 wk; 2) rats exposed to 60% oxygen for 2 wk; 3) rats raised in normoxia for 6 wk; and 4) rats exposed to 60% hyperoxia for 2 wk and to room air for further 4 wk. Normoxic 6-wk rats showed increased D and decreased lacunarity with respect to normoxic 2-wk rats, together with changes in all stereological parameters except for mean alveolar volume. Hyperoxia-exposed 2-wk rats showed significant changes only in total number of alveoli, mean alveolar volume, and lacunarity with respect to equal-in-age normoxic rats. In the comparison between 6-wk rats, the hyperoxia-exposed group showed decreased D and increased lacunarity, together with changes in all stereological parameters except for septal thickness. Analysis of receiver operating characteristic curves showed a comparable discriminatory power of D, lacunarity, and total number of alveoli; Lm and mean alveolar volume were less discriminative. D and lacunarity did not show significant changes when different segmentation thresholds were applied, suggesting that the fractal approach may be fit to automatic image analysis.


Asunto(s)
Displasia Broncopulmonar/patología , Alveolos Pulmonares/patología , Animales , Femenino , Fractales , Hiperoxia/patología , Masculino , Modelos Biológicos , Curva ROC , Ratas Sprague-Dawley
7.
Stem Cells Transl Med ; 13(1): 43-59, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-37963808

RESUMEN

Oxidative stress and fibrosis are important stress responses that characterize bronchopulmonary dysplasia (BPD), a disease for which only a therapy but not a cure has been developed. In this work, we investigated the effects of mesenchymal stromal cells-derived extracellular vesicles (MSC-EVs) on lung and brain compartment in an animal model of hyperoxia-induced BPD. Rat pups were intratracheally injected with MSC-EVs produced by human umbilical cord-derived MSC, following the Good Manufacturing Practice-grade (GMP-grade). After evaluating biodistribution of labelled MSC-EVs in rat pups left in normoxia and hyperoxia, oxidative stress and fibrosis investigation were performed. Oxidative stress protection by MSC-EVs treatment was proved both in lung and in brain. The lung epithelial compartment ameliorated glycosaminoglycan and surfactant protein expression in MSC-EVs-injected rat pups compared to untreated animals. Pups under hyperoxia exhibited a fibrotic phenotype in lungs shown by increased collagen deposition and also expression of profibrotic genes. Both parameters were reduced by treatment with MSC-EVs. We established an in vitro model of fibrosis and another of oxidative stress, and we proved that MSC-EVs suppressed the induction of αSMA, influencing collagen deposition and protecting from the oxidative stress. In conclusion, intratracheal administration of clinical-grade MSC-EVs protect from oxidative stress, improves pulmonary epithelial function, and counteracts the development of fibrosis. In the future, MSC-EVs could represent a new cure to prevent the development of BPD.


Asunto(s)
Displasia Broncopulmonar , Vesículas Extracelulares , Hiperoxia , Células Madre Mesenquimatosas , Recién Nacido , Ratas , Animales , Humanos , Displasia Broncopulmonar/terapia , Distribución Tisular , Vesículas Extracelulares/metabolismo , Fibrosis , Cordón Umbilical/metabolismo , Células Madre Mesenquimatosas/metabolismo , Estrés Oxidativo , Colágeno/metabolismo , Modelos Animales de Enfermedad
8.
Lung ; 190(4): 419-30, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22430123

RESUMEN

BACKGROUND: Moderate normobaric hyperoxia causes alveolar and vascular lung derangement in the newborn rat. Endogenous nitric oxide (NO), which promotes lung growth, is produced from the metabolism of L-arginine to L-citrulline in endothelial cells. We investigated whether administering L-citrulline by raising the serum levels of L-arginine and enhancing NO endogenous synthesis attenuates moderate hyperoxia-induced lung injury. METHODS: Newborn rats were exposed to FiO(2) = 0.6 or room air for 14 days to induce lung derangement and then were administered L-citrulline or a vehicle (sham). Lung histopathology was studied with morphometric features. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected for analysis. Lung vascular endothelial growth factor (VEGF), nitric oxide synthase (eNOS), and matrix metalloproteinase 2 (MMP2) gene and protein expressions were assessed. RESULTS: Serum L-arginine rose in the L-citr + hyperoxia group (p = 0.05), as well as the Von Willebrand factor stained vessels count (p = 0.0008). Lung VEGF immune staining, localized on endothelial cells, was weaker in the sections under hyperoxia than the L-citr + hyperoxia and room air groups. This pattern was comparable with the VEGF gene and protein expression profiles. Mean alveolar size increased in the untreated hyperoxia and sham-treated groups compared with the groups reared in room air or treated with L-citrulline under exposure to hyperoxia (p = 0.0001). Lung VEGF and eNOS increased in the L-citrulline-treated rats, though this treatment did not change MMP2 gene expression but regulated the MMP2 active protein, which rose in BALF (p = 0.003). CONCLUSIONS: We conclude that administering L: -citrulline proved effective in improving alveolar and vascular growth in a model of oxygen-induced pulmonary damage, suggesting better lung growth and matrix regulation than in untreated groups.


Asunto(s)
Citrulina/uso terapéutico , Endotelio Vascular/patología , Hiperoxia/complicaciones , Lesión Pulmonar/etiología , Lesión Pulmonar/prevención & control , Pulmón/irrigación sanguínea , Alveolos Pulmonares/patología , Animales , Animales Recién Nacidos , Arginina/metabolismo , Citrulina/farmacología , Modelos Animales de Enfermedad , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Femenino , Pulmón/metabolismo , Pulmón/patología , Lesión Pulmonar/patología , Metaloproteinasa 2 de la Matriz/metabolismo , Óxido Nítrico/metabolismo , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/metabolismo , Ratas , Ratas Sprague-Dawley , Índice de Severidad de la Enfermedad , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
Cardiol Young ; 22(4): 436-42, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22281050

RESUMEN

OBJECTIVE: To evaluate the effect of a continuous infusion of basic fibroblast growth factor on the adaptive potential of the right ventricular myocardium after 30 days of mechanically induced overload in rats. Materials and methods We banded the pulmonary trunk, so as to increase the systolic workload of the right ventricle, in six Lewis/HanHsd rats at the age of 11 weeks, using six adult rats as controls. The six adult rats were also banded and received an additional continuous infusion of basic fibroblastic growth factor, using six rats with a continuous infusion of basic fibroblastic growth factor only as controls. We analysed the functional adaptation and structural changes of the right ventricular myocardium, blood vessels, and interstitial tissue 30 days after the increased afterload. RESULTS: The pulmonary artery banding induced an increase in the right ventricular free wall thickness of banded rats when compared with controls, which was mainly justified by an increase in cardiomyocyte area and in the percentage of extracellular fibrosis. The infusion of basic fibroblastic growth factor promotes a more extensive capillary network in banded rats (p < 0.001), which modulates the compensatory response of the right ventricle, promoting the hypertrophy of contractile elements and limiting the areas in which fibrosis develops (p < 0.001). CONCLUSIONS: The subcutaneous infusion with osmotic pumps was a valid and reproducible method of delivering basic fibroblast growth factor to heart tissue. This infusion contributed to better preserve the right ventricular capillary network, hampering the development of interstitial fibrosis.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Ventrículos Cardíacos/efectos de los fármacos , Hipertrofia Ventricular Derecha/patología , Remodelación Ventricular/efectos de los fármacos , Adaptación Fisiológica/efectos de los fármacos , Animales , Capilares/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Modelos Animales de Enfermedad , Fibrosis , Infusiones Subcutáneas , Miocardio/patología , Neovascularización Patológica , Ratas , Ratas Endogámicas Lew
10.
J Vis Exp ; (182)2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35435912

RESUMEN

The Ross operation for aortic valve disease has regained new interest due to its outstanding long-term results. Nonetheless, when employed as freestanding root replacement, the possible dilation of the pulmonary autograft and subsequent aortic regurgitation is described. Several animal models have been proposed. However, these are usually limited to ex-vivo models or in-vivo experiments with relatively expensive large animal models. In this study, we sought to establish a rodent model of pulmonary artery graft (PAG) implantation in a systemic position. A total of 39 adult Lewis rats were included. Immediately after euthanasia, the pulmonary root was harvested from a donor animal (n=17). Syngeneic recipient (n=17) and sham-operated (n=5) rats were sedated and ventilated. In the recipient group, the PAG was implanted with an end-to-end anastomosis in infra-renal abdominal aortic position. Sham-operated rats underwent only transection and re-anastomosis of the aorta. Animals were followed with serial ultrasound studies for two months and post-mortem histological analysis. The median PAG diameter in the native position was 3.20 mm (IQR=3.18-3.23). At follow-up, the median diameter of the PAG was 4.03 mm (IQR=3.74-4.13) at 1 week, 4.07 mm (IQR=3.80-4.28) at 1 month, and 4.27 mm (IQR=3.90-4.35) at 2 months (p<0.01). Peak systolic velocity was 220.07 mm/s (IQR=210.43-246.41) at 1 week, 430.88 mm/s (IQR=375.28-495.56) at 1 month, and 373.68 mm/s (IQR=305.78-429.81) at 2 months (p=0.02) and did not differ from the sham-operated group at the end of the experiment (p=0.5). Histological analysis did not show any sign of endothelial thrombosis. This study showed that rodent models may allow for the evaluation of the long-term adaptation of the pulmonary root to a high-pressure system. A systemically placed syngeneic PAG implantation represents a simple and feasible platform for the development and evaluation of novel surgical techniques and drug therapies to further improve the outcomes of the Ross operation.


Asunto(s)
Válvula Pulmonar , Animales , Válvula Aórtica/cirugía , Autoinjertos , Estudios de Seguimiento , Arteria Pulmonar/cirugía , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Ratas , Ratas Endogámicas Lew , Estudios Retrospectivos , Roedores , Trasplante Autólogo
11.
J Clin Med ; 11(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35807025

RESUMEN

Background: The major limitation to the Ross operation is a progressive autograft dilation, possibly leading to reoperations. A murine model was created to evaluate pulmonary artery graft (PAG) adaptation to pressure overload. Methods: Lewis rats (n = 17) underwent heterotopic surgical implantation of a PAG, harvested from syngeneic animals (n = 17). A group of sham animals (n = 7) was used as a control. Seriated ultrasound studies of the PAG were performed. Animals were sacrificed at 1 week (n = 5) or 2 months (n = 15) and the PAG underwent mechanical and histopathological analyses. Results: Echography showed an initial increase in diameter (p < 0.001) and a decrease in peak systolic velocity (PSV). Subsequently, despite no change in diameter, an increase in PSV was observed (p < 0.01). After 1 week, the stiffness of the PAG and the aorta were similar, while at 2 months, the PAG appeared more rigid (p < 0.05). PAG's histological analysis at 2 months revealed intimal hyperplasia development. The tunica media showed focal thinning of the elastic lamellae and normally distributed smooth muscle cells. Conclusions: We demonstrated a stiffening of the PAG wall after its implantation in systemic position; the development of intimal hyperplasia and the thinning of the elastic lamellae could be the possible underlying mechanism.

12.
NPJ Regen Med ; 7(1): 25, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35468920

RESUMEN

The production of skeletal muscle constructs useful for replacing large defects in vivo, such as in congenital diaphragmatic hernia (CDH), is still considered a challenge. The standard application of prosthetic material presents major limitations, such as hernia recurrences in a remarkable number of CDH patients. With this work, we developed a tissue engineering approach based on decellularized diaphragmatic muscle and human cells for the in vitro generation of diaphragmatic-like tissues as a proof-of-concept of a new option for the surgical treatment of large diaphragm defects. A customized bioreactor for diaphragmatic muscle was designed to control mechanical stimulation and promote radial stretching during the construct engineering. In vitro tests demonstrated that both ECM remodeling and fibroblast overgrowth were positively influenced by the bioreactor culture. Mechanically stimulated constructs also increased tissue maturation, with the formation of new oriented and aligned muscle fibers. Moreover, after in vivo orthotopic implantation in a surgical CDH mouse model, mechanically stimulated muscles maintained the presence of human cells within myofibers and hernia recurrence did not occur, suggesting the value of this approach for treating diaphragm defects.

13.
Biomedicines ; 9(7)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206569

RESUMEN

Hydrogels are biomaterials that, thanks to their unique hydrophilic and biomimetic characteristics, are used to support cell growth and attachment and promote tissue regeneration. The use of decellularized extracellular matrix (dECM) from different tissues or organs significantly demonstrated to be far superior to other types of hydrogel since it recapitulates the native tissue's ECM composition and bioactivity. Different muscle injuries and malformations require the application of patches or fillers to replenish the defect and boost tissue regeneration. Herein, we develop, produce, and characterize a porcine diaphragmatic dECM-derived hydrogel for diaphragmatic applications. We obtain a tissue-specific biomaterial able to mimic the complex structure of skeletal muscle ECM; we characterize hydrogel properties in terms of biomechanical properties, biocompatibility, and adaptability for in vivo applications. Lastly, we demonstrate that dECM-derived hydrogel obtained from porcine diaphragms can represent a useful biological product for diaphragmatic muscle defect repair when used as relevant acellular stand-alone patch.

14.
J Mol Cell Cardiol ; 46(5): 653-62, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19162035

RESUMEN

Interstitial cells of the adult rat heart were characterized with respect to i) expression of cardiac markers of commitment and differentiation, ii) myogenic potential in vitro and iii) ability to modulate cardiomyocyte differentiation state. We demonstrate for the first time that fibroblasts and a proportion of pericytes in the adult rat heart express the transcription factor GATA4. This appears to be a peculiar property of the heart. Fibroblasts that are also derived from the splanchnopleuric mesoderm, such as those of the gut, or fibroblasts of different embryological origin, such as those of skin and skeletal muscle, lack this property. Of note, a nestin+/GATA4+ putative stem cell population is also detected in the adult heart. GATA4+ cardiac interstitial cells do not display myogenic potential in vitro. However, cardiac fibroblasts, but not skin fibroblasts, stimulate dedifferentiation of adult cardiomyocytes and their re-entry into the cell cycle in vitro, as demonstrated by the high number of cardiomyocytes expressing Ki67, phosphorylated histone H3 (H3P) and incorporating 5-bromodeoxiuridine (BrdU) in the co-cultures. In conclusion, cardiac fibroblasts have peculiar expression of myogenic transcription factors, a property that may have an impact for reprogramming these cells to the myogenic differentiation. In addition, they are able to modulate the behavior of adult cardiomyocytes, a property that may be used to promote dedifferentiation and proliferation of cardiac cells in the damaged myocardium.


Asunto(s)
Ciclo Celular , Desdiferenciación Celular , Factor de Transcripción GATA4/metabolismo , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Animales , Animales Recién Nacidos , Diferenciación Celular , Células Cultivadas , Fibroblastos/citología , Fibroblastos/metabolismo , Miocardio/citología , Miocardio/metabolismo , Pericitos/citología , Pericitos/metabolismo , Ratas , Ratas Sprague-Dawley
15.
Acta Biomater ; 89: 115-125, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30851456

RESUMEN

Congenital diaphragmatic hernia (CDH) is a neonatal defect in which the diaphragm muscle does not develop properly, thereby raising abdominal organs into the thoracic cavity and impeding lung development and function. Large diaphragmatic defects require correction with prosthetic patches to close the malformation. This treatment leads to a consequent generation of unwelcomed mechanical stress in the repaired diaphragm and hernia recurrences, thereby resulting in high morbidity and significant mortality rates. We proposed a specific diaphragm-derived extracellular matrix (ECM) as a scaffold for the treatment of CDH. To address this strategy, we developed a new surgical CDH mouse model to test the ability of our tissue-specific patch to regenerate damaged diaphragms. Implantation of decellularized diaphragmatic ECM-derived patches demonstrated absence of rejection or hernia recurrence, in contrast to the performance of a commercially available synthetic material. Diaphragm-derived ECM was able to promote the generation of new blood vessels, boost long-term muscle regeneration, and recover host diaphragmatic function. In addition, using a GFP + Schwann cell mouse model, we identified re-innervation of implanted patches. These results demonstrated for the first time that implantation of a tissue-specific biologic scaffold is able to promote a regenerating diaphragm muscle and overcome issues commonly related to the standard use of prosthetic materials. STATEMENT OF SIGNIFICANCE: Large diaphragmatic hernia in paediatric patients require application of artificial patches to close the congenital defect. The use of a muscle-specific decellularized scaffold in substitution of currently used synthetic materials allows new blood vessel growth and nerve regeneration inside the patch, supporting new muscle tissue formation. Furthermore, the presence of a tissue-specific scaffold guaranteed long-term muscle regeneration, improving diaphragm performance to almost complete functional recovery. We believe that diaphragm-derived scaffold will be key player in future pre-clinical studies on large animal models.


Asunto(s)
Matriz Extracelular/trasplante , Hernia Diafragmática/cirugía , Músculo Esquelético , Regeneración , Andamios del Tejido , Aloinjertos , Animales , Femenino , Hernia Diafragmática/metabolismo , Hernia Diafragmática/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Músculo Esquelético/inervación , Músculo Esquelético/fisiología
16.
Cell Transplant ; 17(6): 587-98, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18819247

RESUMEN

Apoptotic phenomena observed in vitro following isolation and following transplantation contribute significantly to islet graft loss. Strategies to reduce apoptosis of islet tissue prior to and posttransplantation may improve graft survival and function and reduce the amount of tissue necessary to achieve insulin independence. The expression of cytoprotective proteins is one such strategy that may prolong islet survival. In this light, heme-oxygenase 1 (HO-1) upregulation has been studied in both allo- and xenotransplantation models. In this study, the effect of HO-1 on apoptosis in neonatal porcine islet-like cell clusters (NPICC) was assessed. In in vitro assessments of NPICC apoptosis, NPICC showed a high sensitivity to apoptotic stimulation using a combination of TNF-alpha and cycloheximide. Stimulation with TNF-alpha alone was sufficient to induce reproducible apoptotic responses as demonstrated by caspase-3,-7 activation and subdiploid DNA analysis. Dose-dependent, high-level HO-1 protein expression was achieved following culture of NPICC in medium containing either cobalt protoporphyrin (CoPP) or cobalt mesoporphyrin (CoMP). CoPP treatment resulted in the reduction of caspase-3,-7 enzyme activity following TNF-alpha stimulation. However, such an effect was not associated with a reduction in the levels of cell death. Indeed, the inhibition of caspase enzyme activity resulted in decreased PARP-1 cleavage, which may lead to heightened levels of necrosis in treated NPICC cultures, possibly explaining the observed commitment of NPICC to the death pathway.


Asunto(s)
Caspasa 3/metabolismo , Caspasa 7/metabolismo , Muerte Celular/fisiología , Islotes Pancreáticos/enzimología , Protoporfirinas/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Animales Recién Nacidos , Muerte Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Cicloheximida/farmacología , Inhibidores de Cisteína Proteinasa/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática , Hemo-Oxigenasa 1/metabolismo , Humanos , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Oligopéptidos/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Inhibidores de la Síntesis de la Proteína/farmacología , Protoporfirinas/metabolismo , Sus scrofa , Factor de Necrosis Tumoral alfa/farmacología
17.
J Invest Surg ; 31(4): 282-291, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28481635

RESUMEN

PURPOSE: Despite a substantial amount of literature on tissue-guided regeneration, decellularization process, repopulation time points and stem cell turnover, more in-depth study on the argument is required. Currently, there are plenty of reports involving large animals, as well as clinical studies facing cardiac repair with decellularized homografts, but no exhaustive rodent models are described. The purpose of this study was to develop such a model in rats; preliminary results are also herein reported. MATERIAL AND METHODS: Fresh or decellularized pulmonary homografts from wild type rats were implanted in the abdominal aorta of green fluorescent protein positive rats. Three experimental groups were build up: sham, fresh homograft recipients and decellularized homograft recipients. The homograft decellularization process was performed with three cycles of detergent-enzymatic treatment protocol. Surgical technique of pulmonary homograft implantation and postoperative ultrasonographic evaluation were also reported; gross, histology and immunohistochemistry analysis on unimplanted and postoperative homografts were also carried out. RESULTS: The median total recipient operating time was 148 minutes, with a surgical success rate of 82%. The decellularization protocol resulted effective and showed a complete decellularization with intact extracellular matrix. At 15 days from surgery, the implanted decellularized pulmonary homografts exhibited cell repopulation in the outer media wall and partial endothelial lining in absence of rejection. CONCLUSIONS: Our technique is a feasible and reproducible model that can be fundamental for building a valid study for further exploitation on the field. Even in a short-term follow up, the decellularized pulmonary homografts showed autologous repopulation in absence of rejection.


Asunto(s)
Aloinjertos/trasplante , Modelos Animales , Arteria Pulmonar/trasplante , Ratas , Aloinjertos/diagnóstico por imagen , Animales , Matriz Extracelular/trasplante , Estudios de Factibilidad , Femenino , Rechazo de Injerto/epidemiología , Masculino , Tempo Operativo , Arteria Pulmonar/diagnóstico por imagen , Ratas Sprague-Dawley , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/métodos , Resultado del Tratamiento , Ultrasonografía
18.
FASEB J ; 20(14): 2534-6, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17077278

RESUMEN

Cardiomyocytes expressing host markers, such as the Y chromosome in sex-mismatched transplants, have been described in human allografts, suggesting that circulating cells can contribute to cardiac regeneration. It has not been established, however, whether host-derived cardiomyocytes result from transdifferentiation of stem cells or cell fusion. To address this issue, we used heterotopic heart xenografts and looked for markers of donor and recipient cells. Golden Syrian hamsters or transgenic mice expressing nuclear beta-galactosidase under the control of the cardiac troponin I promoter served as organ donors, while GFP+ transgenic rats were used as recipients. GFP+ cells, including abundant CD-45+ inflammatory cells and rare undifferentiated cells expressing early cardiac markers (GATA-4 or MEF2C), were found in xenografts harvested two weeks after surgery. In addition, rare GFP+ mature cardiomyocytes were found in 7 of 8 hamster xenografts and 6 of 6 mouse xenografts. The proportion of these cells was very low (0.0001% to 0.0344% in hamster xenografts) but similar to the one observed in control rat heart allografts. Without exception, all GFP+ cardiomyocytes also expressed donor markers, i.e., hamster membrane antigens or lacZ, so they must derive from cell fusion, not transdifferentiation.


Asunto(s)
Fusión Celular , Trasplante de Corazón , Miocitos Cardíacos/metabolismo , Trasplante Heterólogo , Animales , Animales Modificados Genéticamente , Biomarcadores , Cricetinae , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones , Miocardio/citología , Miocardio/metabolismo , Ratas , Ratas Sprague-Dawley , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
19.
Cardiovasc Res ; 68(3): 394-404, 2005 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16023094

RESUMEN

OBJECTIVES: The aim of this study was to investigate the contribution of host-derived circulating cells to cardiac repair after tissue damage using the model of heterotopic heart transplantation between transgenic recipient rats expressing green fluorescent protein (GFP) and wild-type donors. METHODS: Unlabeled donor rat hearts, some of which underwent prolonged cold ischemia pretreatment, were transplanted into the abdominal cavity of GFP+ transgenic recipient rats and were analyzed 15 and 90 days after surgery. An additional experimental group underwent heart transplantation following administration of granulocyte-colony stimulatory factor (G-CSF) to mobilize bone marrow cells. RESULTS: Most transplants contained GFP+ mature cardiomyocytes. However, systematic counting in the transplants showed that the proportion of GFP+ cardiomyocytes was only 0.0005% to 0.008% of all cardiomyocytes. These relative proportions did not change after G-CSF treatment, despite evidence for sustained marrow cell mobilization. Confocal image analysis showed that the majority of GFP+ cardiomyocytes contained a high number of nuclei, suggesting that these cells may derive from fusion events. Very rarely, small GFP+ undifferentiated cells, expressing GATA-4, were also identified. Occasionally, GFP+ endothelial cells, but not smooth muscle cells, were detected in blood vessels of some transplants. CONCLUSIONS: Our results demonstrate that cardiomyocytes expressing a host transgenic marker are detectable in heterotopic heart transplants; however, they do not significantly contribute to repopulation of the damaged myocardium.


Asunto(s)
Trasplante de Corazón , Miocitos Cardíacos/citología , Regeneración , Animales , Animales Modificados Genéticamente , Biomarcadores/análisis , Células de la Médula Ósea/citología , Recuento de Células , Fusión Celular , ADN/análisis , Células Endoteliales/patología , Femenino , Citometría de Flujo , Factor de Transcripción GATA4/análisis , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Movilización de Célula Madre Hematopoyética , Procesamiento de Imagen Asistido por Computador , Masculino , Microscopía Confocal , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas , Ratas Sprague-Dawley , Trasplante Heterotópico/patología
20.
Brain Struct Funct ; 220(1): 229-47, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24135771

RESUMEN

Premature newborns may be exposed to hyperoxia in the first postnatal period, but clinical and experimental works have raised the question of oxygen toxicity for the developing brain. However, specific analysis of hyperoxia exposure on neurogenesis is still lacking. Thus, the aim of the present study was to evaluate possible changes in the morphometric parameters of the main neurogenic sites in newborn rats exposed to 60 or 95 % oxygen for the first 14 postnatal days. The optical disector, a morphometric method based upon unbiased sampling principles of stereology, was applied to analyse cell densities, total volumes, and total cell numbers of the dentate gyrus (DG) and subventricular zone (SVZ). Apoptosis and proliferation were also studied by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling method and anti-ki67 immunohistochemistry, respectively. Severe hyperoxia increased the percentage of apoptotic cells in the DG. Moderate and severe hyperoxia induced a proliferative response both in the DG and SVZ, but the two neurogenic sites showed different changes in their morphometric parameters. The DG of both the hyperoxic groups showed lower volume and total cell number than that of the normoxic one. Conversely, the SVZ of newborn rats exposed to 95 % hyperoxia showed statistically significant higher volume and total cell number than SVZ of rats raised in normoxia. Our findings indicate that hyperoxia exposure in the first postnatal period affects both the neurogenic areas, although in different ways, i.e. reduction of DG and expansion of SVZ.


Asunto(s)
Apoptosis/fisiología , Giro Dentado/fisiopatología , Hiperoxia/patología , Ventrículos Laterales/fisiopatología , Animales , Animales Recién Nacidos , Bromodesoxiuridina , Recuento de Células , Giro Dentado/patología , Femenino , Etiquetado Corte-Fin in Situ , Antígeno Ki-67/metabolismo , Ventrículos Laterales/patología , Masculino , Ratas , Ratas Sprague-Dawley , Estadísticas no Paramétricas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA