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Extracellular matrix (ECM) rich whole organ bio-scaffolds, preserving structural integrity and essential growth factors, has potential towards regeneration and reconstruction. Women with cervical anomalies or trauma can benefit from clinical cervicovaginal repair using constructs rich in site specific ECM. In this study, complete human cervix decellularization was achieved using a modified perfusion-based stir bench top decellularization method. This was followed by physico-chemical processes including perfusion of ionic agents, enzymatic treatment and washing using detergent solutions for a duration of 10-12 d. Histopathological analysis, as well as DNA quantification confirmed the efficacy of the decellularization process. Tissue ultrastructure integrity was preserved and the same was validated via scanning electron microscopy and transmission electron microscopy studies. Biochemical analysis and structural characterizations like Fourier transform infrared, Raman spectroscopy of decellularized tissues demonstrated preservation of important proteins, crucial growth factors, collagen, and glycosaminoglycans.In vitrostudies, using THP-1 and human umbilical vein endothelial cell (HUVEC) cells, demonstrated macrophage polarization from M1 to M2 and vascular functional genes enhancement, respectively, when treated with decellularized human cervical matrix (DHCp). Crosslinked DHC scaffolds were recellularized with site specific human cervical epithelial cells and HUVEC, showing non-cytotoxic cell viability and enhanced proliferation. Furthermore, DHC scaffolds showed immunomodulatory effectsin vivoon small rodent model via upregulation of M2 macrophage genes as compared to decellularized rat cervix matrix scaffolds (DRC). DHC scaffolds underwent neo-vascularization followed by ECM remodeling with enhanced tissue integration.
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Cuello del Útero , Matriz Extracelular Descelularizada , Células Endoteliales de la Vena Umbilical Humana , Andamios del Tejido , Humanos , Femenino , Cuello del Útero/citología , Animales , Matriz Extracelular Descelularizada/química , Matriz Extracelular Descelularizada/farmacología , Andamios del Tejido/química , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Ratas , Ingeniería de Tejidos , Células THP-1 , Macrófagos/metabolismo , Macrófagos/citología , Ratas Sprague-DawleyRESUMEN
Autonomization is a physiological process allowing a flap to develop neo-vascularization from the reconstructed wound bed. This phenomenon has been used since the early application of flap surgeries but still remains poorly understood. Reconstructive strategies have greatly evolved since, and fasciocutaneous flaps have progressively replaced muscle-based reconstructions, ensuring better functional outcomes with great reliability. However, plastic surgeons still encounter challenges in complex cases where conventional flap reconstruction reaches its limitations. Furthermore, emerging bioengineering applications, such as decellularized scaffolds allowing a complex extracellular matrix to be repopulated with autologous cells, also face the complexity of revascularization. The objective of this article is to gather evidence of autonomization phenomena. A systematic review of flap autonomization is then performed to document the minimum delay allowing this process. Finally, past and potential applications in bio- and tissue-engineering approaches are discussed, highlighting the potential for in vivo revascularization of acellular scaffolds.
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Klotho (Kl) is considered an antiaging gene, mainly for the inhibition of the insulin-like growth factor-1 signaling. Kl exists as full-length transmembrane, which acts as co-receptor for fibroblast growth factor receptor, and in soluble forms (sKl). The sKl may exert pleiotropic effects on organs and tissues by regulating several pathways involved in the pathogenesis of diseases associated with oxidative and inflammatory state. In diabetic Patients, serum levels of Kl are significantly decreased compared to healthy subjects, and are related to duration of diabetes. In diabetic retinopathy (DR), one of the most common microvascular complications of type 2 diabetes, serum Kl levels are negatively correlated with progression of the disease. A lot of evidences showed that Kl regulates several mechanisms involved in maintaining homeostasis and functions of retinal cells, including phagocytosis, calcium signaling, secretion of vascular endothelial growth factor A (VEGF-A), maintenance of redox status, and melanin biosynthesis. Experimental data have been shown that Kl exerts positive effects on several mechanisms involved in onset and progression of DR. In particular, treatment with Kl: (1) Prevents apoptosis induced by oxidative stress in human retinal endothelial cells and in retinal pigment epithelium (RPE) cells; (2) reduces secretion of VEGF-A by RPE cells; and (3) decreases subretinal fibrosis and preserves autophagic activity. Therefore, Kl may become a novel biomarker and a good candidate for the treatment of DR.
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BACKGROUND: Moyamoya disease (MMD) is a rare cause of acute stroke and transient ischemic attacks in children. We described clinical, diagnostic features and follow-ups of a young child with acute stroke. CASE SUMMARY: We report a 4-year-old girl with left hemiparesis after an acute ischemic stroke. Her history was also significant for repeated left or right focal motor seizures, generalized tonic-clonic convulsions and transient ischemic attacks. Her magnetic resonance imaging and computed tomography (CT) of the brain and magnetic resonance angiography, CT angiography and venography on the cerebral vessels revealed evidence of bilateral fronto-parietal ischemic infarctions, occlusion of the right and left internal carotid arteries started at its bifurcation and non-visualization of right and left anterior and middle cerebral arteries. There was evidence of progression in angiography manifested as development of collaterals from the basal perforating vessels, increase in the extent of large intracranial arterial stenosis/occlusion and extensive collateral circulation with predominance from the posterior circulation. Physical and neurological evaluation and comprehensive laboratory investigations excluded an obvious comorbid disease or risk factor for the child's condition. The diagnosis of MMD was highly suggested as a cause of the child's steno-occlusive condition. She was treated symptomatically with levetiracetam, an antiepileptic medication. Aspirin was prescribed for secondary prevention. Her clinical manifestations were improved during the three years of follow-up. Revascularization surgery was postponed. CONCLUSION: Up to our knowledge, this is the first report for MMD in a child in our country. The clinical improvement and the stabilization of the child's condition over the 3 years of follow-up could be attributed to the rapid and extensive recruitment of collaterals and absence of risk factors or comorbidities. Revascularization surgery is highly recommended.
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Pre-vascularization has been receiving significant attention for developing implantable engineered 3D tissues. While various pre-vascularization techniques have been developed to improve graft vascularization, the effect of pre-vascularized patterns onin vivoneo-vessel formation has not been studied. In this study, we developed a functional pre-vascularized construct that significantly promotes graft vascularization and conductedin vivoevaluations of the micro-vascular patterns (µVPs) in various printed designs.µVP formation, composed of high-density capillaries, was induced by the co-printing of endothelial cells and adipose-derived stem cells (ADSC). We implanted the printed constructs with variousµVP designs into a murine femoral arteriovenous bundle model and evaluated graft vascularization via 3D visualization and immune-histological analysis of the neo-vessels. TheµVP-distal group (µVP located away from the host vessel) showed approximately two-fold improved neo-vascularization compared to theµVP-proximal group (µVP located near the host vessel). Additionally, we confirmed that theµVP-distal group can generate the angiogenic factor gradient spatial environment for graft vascularization via computational simulations. Based on these results, the ADSC mono pattern (AMP), which secretes four times higher angiogenic factors thanµVP, was added to theµVP + AMP group design. TheµVP + AMP group showed approximately 1.5- and 1.9-fold higher total sprouted neo-vessel volume than theµVP only and AMP only groups, respectively. In immunohistochemical staining analysis, theµVP + AMP group showed two-fold improved density and diameter of the matured neo-vessels. To summarize, these findings demonstrate graft vascularization accelerated due to design optimization of our pre-vascularized constructs. We believe that the developed pre-vascularization printing technique will facilitate new possibilities for the upscaling of implantable engineered tissues/organs.
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Bioimpresión , Ratones , Animales , Células Endoteliales , Neovascularización Fisiológica , Ingeniería de Tejidos/métodos , Andamios del Tejido , Impresión TridimensionalRESUMEN
PURPOSE: Glioblastoma multiforme (GBM) is the most common glioma and standard therapies can only slightly prolong the survival. Neo-vascularization is a potential target to image tumor microenvironment, as it defines its brain invasion. We investigate [18F]rhPSMA-7.3 with PET/MRI for quantitative imaging of neo-vascularization in GBM bearing mice and human tumor tissue and compare it to [18F]FET and [18F]fluciclovine using PET pharmacokinetic modeling (PKM). METHODS: [18F]rhPSMA-7.3, [18F]FET, and [18F]fluciclovine were i.v. injected with 10.5 ± 3.1 MBq, 8.0 ± 2.2 MBq, 11.5 ± 1.9 MBq (n = 28, GL261-luc2) and up to 90 min PET/MR imaged 21/28 days after surgery. Regions of interest were delineated on T2-weighted MRI for (i) tumor, (ii) brain, and (iii) the inferior vena cava. Time-activity curves were expressed as SUV mean, SUVR and PKM performed using 1-/2-tissue-compartment models (1TCM, 2TCM), Patlak and Logan analysis (LA). Immunofluorescent staining (IFS), western blotting, and autoradiography of tumor tissue were performed for result validation. RESULTS: [18F]rhPSMA-7.3 showed a tumor uptake with a tumor-to-background-ratio (TBR) = 2.1-2.5, in 15-60 min. PKM (2TCM) confirmed higher K1 (0.34/0.08, p = 0.0012) and volume of distribution VT (0.24/0.1, p = 0.0017) in the tumor region compared to the brain. Linearity in LA and similar k3 = 0.6 and k4 = 0.47 (2TCM, tumor, p = ns) indicated reversible binding. K1, an indicator for vascularization, increased (0.1/0.34, 21 to 28 days, p < 0.005). IFS confirmed co-expression of PSMA and tumor vascularization. [18F]fluciclovine showed higher TBR (2.5/1.8, p < 0.001, 60 min) and VS (1.3/0.7, p < 0.05, tumor) compared to [18F]FET and LA indicated reversible binding. VT increased (p < 0.001, tumor, 21 to 28 days) for [18F]FET (0.5-1.4) and [18F]fluciclovine (0.84-1.5). CONCLUSION: [18F]rhPSMA-7.3 showed to be a potential candidate to investigate the tumor microenvironment of GBM. Following PKM, this uptake was associated with tumor vascularization. In contrast to what is known from PSMA-PET in prostate cancer, reversible binding was found for [18F]rhPSMA-7.3 in GBM, contradicting cellular trapping. Finally, [18F]fluciclovine was superior to [18F]FET rendering it more suitable for PET imaging of GBM.
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Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias de la Próstata , Masculino , Humanos , Animales , Ratones , Glioblastoma/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/metabolismo , Tirosina/farmacocinética , Microambiente TumoralRESUMEN
Mesangiogenic progenitor cells (MPCs) have been isolated from human bone marrow (BM) mononuclear cells. They attracted particular attention for the ability to differentiate into exponentially growing mesenchymal stromal cells while retaining endothelial differentiative potential. MPC power to couple mesengenesis and angiogenesis highlights their tissue regenerative potential and clinical value, with particular reference to musculoskeletal tissues regeneration. BM and adipose tissue represent the most promising adult multipotent cell sources for bone and cartilage repair, although discussion is still open on their respective profitability. Culture determinants, as well as tissues of origin, appeared to strongly affect the regenerative potential of cell preparations, making reliable methods for cell isolation and growth a prerequisite to obtain cell-based medicinal products. Our group had established a definite consistent protocol for MPC culture, and here, we present data showing MPCs to be tissue specific.
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Age-related macular degeneration (AMD) is among the world's leading causes of blindness. In its neovascular form (nAMD), around 25% of patients present further anatomical and visual deterioration due to persistence of neovascular activity, despite gold-standard treatment protocols using intravitreal anti-VEGF medications. Thus, to comprehend, the molecular pathways that drive choroidal neoangiogenesis, associated with the vascular endothelial growth factor (VEGF), are important steps to elucidate the mechanistic events underneath the disease development. This is a pilot study, a prospective, translational experiment, in a real-life context aiming to evaluate the protein profiles of the aqueous humor of 15 patients divided into three groups: group 1, composed of patients with nAMD, who demonstrated a good response to anti-VEGF intravitreal injections during follow-up (good responsive); group 2, composed of patients with anti-VEGF-resistant nAMD, who demonstrated choroidal neovascularization activity during follow-up (poor/non-responsive); and group 3, composed of control patients without systemic diseases or signs of retinopathy. For proteomic characterization of the groups, mass spectrometry (label-free LC-MS/MS) was used. A total of 2,336 proteins were identified, of which 185 were distinctly regulated and allowed the differentiation of the clinical conditions analyzed. Among those, 39 proteins, including some novel ones, were analyzed as potential disease effectors through their pathophysiological implications in lipid metabolism, oxidative stress, complement system, inflammatory pathways, and angiogenesis. So, this study suggests the participation of other promising biomarkers in neovascular AMD, in addition to the known VEGF.
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The pathogenesis of bowel endometriosis is multifactorial. There is a predilection for disease of the rectum/sigmoid colon because refluxed endometrium is more likely to settle in the pouch of Douglas and its movement is delimited by the sigmoid colon, in addition to the close proximity of the rectum/sigmoid to posterior extrinsic uterine adenomyosis and to ovarian endometriomas. Once situated, deep bowel endometriosis has features of invasion, angiogenesis, and fibrosis (repeated tissue injury and repair), with emerging research on oxidative stress and the microbiome. Furthermore, deep bowel endometriosis is associated with neurogenesis and/or the recruitment of local nerve fibers and is capable of invading existing nerves, which in turn may also promote fibrosis. Recently, somatic cancer driver mutations (e.g., in KRAS) were identified in deep bowel endometriosis, which may play a role in the genetic/epigenetic theory of endometriosis. In the future, it is possible that bowel endometriosis could be classified based on molecular features.
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Adenomiosis , Endometriosis , Neoplasias , Endometrio , Femenino , Humanos , RectoRESUMEN
Alternative splicing leads to the secretion of multiple forms of vascular endothelial growth factor-A (VEGF-A) that differ in their activity profiles with respect to neovascularization. FSAP (factor VII activating protease) is the zymogen form of a plasma protease that is activated (FSAPa) upon tissue injury via the release of histones. The purpose of the study was to determine if FSAPa regulates VEGF-A activity in vitro and in vivo. FSAP bound to VEGF165, but not VEGF121, and VEGF165 was cleaved in its neuropilin/proteoglycan binding domain. VEGF165 cleavage did not alter its binding to VEGF receptors but diminished its binding to neuropilin. The stimulatory effects of VEGF165 on endothelial cell proliferation, migration, and signal transduction were not altered by FSAP. Similarly, proliferation of VEGF receptor-expressing BAF3 cells, in response to VEGF165, was not modulated by FSAP. In the mouse matrigel model of angiogenesis, FSAP decreased the ability of VEGF165, basic fibroblast growth factor (bFGF), and their combination, to induce neovascularization. Lack of endogenous FSAP in mice did not influence neovascularization. Thus, FSAP inhibited VEGF165-mediated angiogenesis in the matrigel model in vivo, where VEGF's interaction with the matrix and its diffusion are important.
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Neovascularización Patológica/metabolismo , Serina Endopeptidasas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Colágeno/metabolismo , Combinación de Medicamentos , Femenino , Factores de Crecimiento de Fibroblastos/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inmunofilinas/metabolismo , Laminina/metabolismo , Ratones , Ratones Endogámicos C57BL , Unión Proteica/fisiología , Proteoglicanos/metabolismo , Transducción de Señal/fisiologíaRESUMEN
BACKGROUND: Neo-vascularization, an indispensible phenomenon for tissue regeneration, facilitates repair and remodeling of wound tissues. This process is impaired in chronic wounds due to reduced number and recruitment of endothelial cells (ECs), thereby necessitating development of newer strategies to enhance the EC repertoire as a therapeutic approach. METHODS: We explored the 'plasticity' of Wharton's jelly derived-mesenchymal stromal cells (WJ-MSCs) using an anti-inflammatory drug-mediated enhanced trans-differentiation into ECs, based on our observation of temporal decrease in COX-2 expression during trans-differentiation of MSCs into ECs at day 7 and 14 along with mature ECs. RESULTS: At a physiological level, an increased DiI-labeled acetylated-low density lipoprotein (DiI-Ac-LDL) uptake, proliferation, migration and chick chorio allantoic membrane (CAM)-vasculogenesis occurred while at a molecular level significant up-regulation in messenger RNA (mRNA) and protein expression of endothelial-specific markers, Vegfr2, Pecam, eNOS, VE-Cadh and Tie-2, along with an activated p-VEGFR2 and its downstream mediators were observed in celecoxib-preconditioned ECs as compared with WJ-MSCs. Green fluorescent protein (GFP)-expressing stable WJ-MSCs and trans-differentiated EC-D14 in the absence/presence of celecoxib were generated using antibiotic selection for intradermal transplantation at the wound site on a murine 'excisional splinting wound' model. Engraftment of transplanted human cells in immunosuppressant-treated mice was confirmed by a significant increase in the expression levels of human gene-specific endothelial markers at the regenerated wound sites. Morphometrically, increased vascularity and percent wound closure were observed in regenerated wounds of mice transplanted with celecoxib-preconditioned-EC-D14. CONCLUSION: Cox-2 inhibition led to an enhanced trans-differentiation of WJ-MSCs into ECs that, when transplanted, accelerated the skin regeneration by engraftment and neo-vascularization at the wound bed, suggesting a plausible new therapeutic role of celecoxib.
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Plasticidad de la Célula/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Células Endoteliales/metabolismo , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Neovascularización Fisiológica/fisiología , Gelatina de Wharton/citología , Cicatrización de Heridas/fisiología , Animales , Biomarcadores/metabolismo , Celecoxib/farmacología , Embrión de Pollo , Inhibidores de la Ciclooxigenasa 2/farmacología , Endotelio/metabolismo , Femenino , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/metabolismo , Transgenes/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Age-related Macular Degeneration (AMD) is one of the common diseases affecting the posterior part of the eye, of a large population above 45 years old. Anti-Vascular Endothelial Growth Factor- A (Anti-VEGF-A) agents have been considered and approved as therapeutic agents for the treatment of AMD. Due to the large molecular weight and poor permeability through various eye membranes, VEGF-A inhibitors are given through an intravitreal injection, even though the delivery of small therapeutic molecules by topical application to the posterior part of the eye exhibits challenges in the treatment. To overcome these limitations, nanocarrier based delivery systems have been utilized to a large extent for the delivery of therapeutics. Nanocarriers system offers prodigious benefits for the delivery of therapeutics to the posterior part of the eye in both invasive and non-invasive techniques. The nano size can improve the permeation of therapeutic agent across the biological membranes. They provide protection from enzymes present at the site, targeted delivery or binding with the disease site and extend the release of therapeutic agents with prolonged retention. This leads to improved therapeutic efficacy, patient compliance, and cost effectiveness of therapy with minimum dose associated side-effects. This review has summarized various nanocarriers explored for the treatment of AMD and challenges in translation.
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Sistemas de Liberación de Medicamentos , Degeneración Macular/tratamiento farmacológico , Nanoestructuras , Administración Oftálmica , Animales , Portadores de Fármacos/química , Humanos , Inyecciones Intravítreas , Degeneración Macular/fisiopatología , Persona de Mediana Edad , Tamaño de la Partícula , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
PURPOSE: To describe the histopathologic features of an early case of presumably bilateral polypoidal choroidal vasculopathy (PCV) in two eyes obtained at autopsy from a patient with no prior ocular therapy. OBSERVATIONS: The choroid of both eyes at the macular and peripapillary regions was greatly thickened with dilated, thin walled choroidal venules intertwining with arteriosclerotic arterioles in the Sattler's layer of the choroidal vasculature. At the temporal and nasal equatorial regions of both eyes many of these congested venular channels abruptly disappeared and were replaced by loose connective tissue with loss of the normal choroidal stromal tissue and uveal melanocytes. A few remaining venules showed intraluminal sloughing of endothelial cells and deposition of fibrinous material networks suggesting occlusion of these choroidal venules. At this equatorial location, serous detachment of retinal pigment epithelium (RPE) appeared and a thin neovascular membrane with cords of endothelial cell invaded into the sub-RPE space. Anteriorly, the neovascular membrane expanded and bulged into the sub-retinal space with dilated neovascular capillaries in a "grape like" or polypoidal configuration. CONCLUSION AND IMPORTANCE: Polypoidal Choroidal Vasculopathy is a disease of the dilated and multi-layered choroidal venules. Occlusion of these choroidal vascular channels might give rise to choroidal stasis and ischemia leading to serous RPE detachment and a sub-RPE neovascular membrane. Gross dilatation of the choroidal venules and capillaries in the sub-RPE neovascular membrane leads to the characteristic "grape like" structures, a unique clinical feature in this disease entity. These pathologic features of PCV are different from the pathologic changes of neovascular age-related macular degeneration (nAMD). Consequently, PCV and nAMD are two distinct diseases. However, in the late stage of both entities, choroidal ischemia in both diseases, lead to sub-RPE neovascularization and subsequent sub-RPE and/or sub-retinal hemorrhage. These results in both entities showed comparable clinical and pathologic features that are frequently mistaken PCV as a sub-type of Neovascular AMD.
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In this study, an injectable chitosan-hyaluronic acid (CS-HA) based hydrogel was designed incorporating pro-angiogenic molecule, deferoxamine loaded PLGA nanoparticles (DFO NPs), for enhancing angiogenesis. DFO-NPs were prepared by double emulsion solvent diffusion technique and characterized for their physicochemical properties. The DLS and SEM analysis showed an average particle size of 220±71nm with spherical morphology and the encapsulation efficiency was found to be 30±5%. An ECM mimicking chitosan-hyaluronic acid (CS-HA) coacervate hydrogel was prepared. Both free DFO and DFO NPs were entrapped into the prepared CS-HA composite hydrogel. The hydrogels were characterized by SEM, FTIR and Rheology. Addition of DFO NPs did not affect the injectablility and flowability of developed hydrogels. In vitro DFO release from the prepared composite hydrogels showed controlled release over a period of 10days. Both the hydrogel systems showed excellent cyto-compatability and good cell proliferation for rASCs as well as HUVECs. The DFO and DFO NPs loaded composite hydrogels revealed effective tube formation in comparison with control hydrogels without DFO and DFO NPs. The in vivo angiogenic evaluation of the free DFO and DFO NPs (0.025%w/w) loaded composite hydrogels were studied by injecting the developed hydrogel subcutaneously into mice for 2-4 weeks. The DFO NPs loaded composite hydrogel had enhanced neovascularization when compared to control gels. Thus, the developed DFO NPs loaded composite hydrogel could potentially be used for therapeutic angiogenesis.
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Quitosano/química , Deferoxamina/administración & dosificación , Ácido Hialurónico/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanopartículas/administración & dosificación , Neovascularización Fisiológica/efectos de los fármacos , Animales , Células Cultivadas , Deferoxamina/química , Deferoxamina/farmacocinética , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Liberación de Fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Inyecciones , Ácido Láctico/química , Ratones Endogámicos BALB C , Nanopartículas/química , Tamaño de la Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido PoliglicólicoRESUMEN
Aims: Stem cells exposed to pathological levels of reactive oxygen species (ROS) at wound sites fail to regenerate tissue. The molecular mechanism underlying differential levels of ROS-mediated regulation of stem cells remains elusive. This study elucidates the mechanistic role of catalase at 10 µM H2O2-induced proliferation of mouse bone marrow stromal (BMSC) and hematopoietic (HSPC) stem/progenitor cells. Results: BMSCs and HSPCs depicted an increased growth rate and colony formation, in the presence of 10 µM but not 100 µM concentration of H2O2, an effect that was perturbed by Vit. C. Mechanistically, JNK activation-FOXO3a nuclear translocation and binding of FOXO3a to catalase promoter at 10 µM H2O2 led to an increased expression and activity of anti-oxidant gene, catalase. This was followed by an increased proliferative phenotype via the AKT-dependent pathway that was perturbed in the presence of catalase-inhibitor, 3-aminotriazole due to an increased ROS-mediated inactivation of AKT. Preclinically, 10 µM H2O2-mediated preconditioning of BMSCs/HSPCs transplantation accelerated wound closure, enhanced catalase expression, and decreased ROS levels at the wound site. Transplantation of male donor cells into female recipient mice or GFP-labeled BMSCs or HSPCs depicted an increased engraftment and proliferation in preconditioned cell transplanted groups as compared with the wound control. Wound healing occurred via keratinocyte generation and vascularization in preconditioned BMSCs, whereas only neo-vascularization occurred in the preconditioned HSPCs transplanted groups. Innovation and Conclusion: Our study suggests a distinct role of catalase that protects BMSCs and HSPCs from low ROS and promotes proliferation. Transplantation of preconditioned stem cells enhanced wound tissue regeneration with a better antioxidant defense mechanism-as a therapeutic approach in stem cell transplantation-mediated tissue regeneration. Antioxid. Redox Signal. 28, 1047-1065.
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Bone marrow endothelial progenitor cells (EPCs) have shown a great promise to promote ischemic tissue neovascularization and to attenuate ischemic injury in a variety of animal models, which led to EPC-based clinical trials that yielded modest but promising results. Some of the variables in the use of EPCs relate to their differential isolation and characterization protocols since the EPC literature does not identify a unique marker for these vascular progenitors. In this chapter, we present step-by-step protocols for the isolation of EPCs, their characterization and culture conditions, and their potential use in basic and clinical research.
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Separación Celular , Células Progenitoras Endoteliales/citología , Células Progenitoras Endoteliales/metabolismo , Animales , Biomarcadores , Diferenciación Celular , Separación Celular/métodos , Células Endoteliales/citología , Células Endoteliales/metabolismo , Ratones , Neovascularización Fisiológica , Regeneración , Investigación , Trasplante de Células MadreRESUMEN
Aim Toinvestigatetheeffectofrecombi-nant snake venom metalloproteinase inhibitor (rSVM-PI ) on neovascularization and its molecular mecha-nism.Methods Chickenchorioallantoicmembrane (CAM)assay was used to examine the antiangiogenic effect of rSVMPI.Alamar blue analysis was used to de-tect cell proliferation.Annexin V-FITC double labeling flow cytometry was used to assay cell apoptosis. Scratch marker was used to assay cell migration.Boy-den chamber analysis method was used to detect cells chemotaxis in vitro.Tube like structure(TLS)of HU-VECs was used to detect the ability of neovasculariza-tion in vitro.Real-time PCR and Western blot were used to assay the expressions of KDR and FGFR-1 inHUVECs. Results Thevasculardensityindex (VDI)of CAM was drastically decreased after rSVMPI treatment, chemotaxis of HUVECs in response of VEGF was inhibited in the presence of rSVMPI,TLS of HUVECs was less than control group.The expres-sions of KDR and FGFR-1 were down-regulated by re-al-timePCRandWesternblotassay.Conclusion rS-VMPI may inhibit neovascularization by blocking the VEGF-KDR or bFGF-FGFR signal transduction path-way.
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Wound healing by cell transplantation techniques often suffer setbacks due to oxidative stress encountered at injury sites. A porous polyethyleneglycol-polyurethane (PEG-PU) scaffold that facilitates cell delivery and boosts tissue repair was developed through semi-interpenetrating polymer network approach. The key physico-chemical properties assessed confirms these polymeric matrices are highly thermostable, barostable, degrade at an acidic pH (5.8), biodegradable, cytocompatible and possess excellent porosity. Mechanism of cellular penetration into porous polymer networks was evident by a ≥6 - fold increase in gene expression of MMP-13 and MMP-2 via activation of Akt and Erk. H2O2-induced apoptosis of mouse bone marrow stem cells (BMSCs) was abrogated in presence of polymer networks indicating a protective effect from oxidative stress. Transplantation of BMSC + PEG-PU at murine excisional splint wound site depicted significant increase in fibroblast proliferation, collagen deposition, anti-oxidant enzyme activities of catalase, SOD and GPx. Furthermore it significantly decreased expression of pro-inflammatory cytokines (IL-1ß, TNF-α, IL-8, etc) with a concomitant increase in anti-inflammatory cytokines (IL-10, IL-13) at an early healing period of day 7. Finally, immunostaining revealed an enhanced engraftment and vascularity indicating an accelerated wound tissue closure. This pre-clinical study demonstrates the proof-of-concept and further necessitates their clinical evaluation as potential cell delivery vehicle scaffolds.
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Materiales Biocompatibles/química , Células de la Médula Ósea/citología , Éteres/química , Polietilenglicoles/química , Poliuretanos/química , Trasplante de Células Madre , Células Madre/citología , Andamios del Tejido , Cicatrización de Heridas , Heridas y Lesiones/terapia , Implantes Absorbibles , Animales , Apoptosis/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Catalasa/biosíntesis , Catalasa/genética , Adhesión Celular , Línea Celular Tumoral , Colágeno/metabolismo , Fibroblastos/citología , Glutatión Peroxidasa/biosíntesis , Glutatión Peroxidasa/genética , Humanos , Interleucinas/biosíntesis , Interleucinas/genética , Ensayo de Materiales , Metaloproteinasa 13 de la Matriz/biosíntesis , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 2 de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo , Porosidad , Células Madre/metabolismo , Superóxido Dismutasa/biosíntesis , Superóxido Dismutasa/genética , Andamios del Tejido/química , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Autologous saphenous veins are commonly used for the coronary artery bypass grafting even if they are liable to progressive patency reduction, known as 'vein graft disease'. Although several cellular and molecular causes for vein graft disease have been identified using in vivo models, the metabolic cues induced by sudden interruption of vasa vasorum blood supply have remained unexplored. In the present manuscript, we describe the design of an ex vivo culture system allowing the generation of an oxygen gradient between the luminal and the adventitial sides of the vein. This system featured a separation between the inner and the outer vessel culture circuits, and integrated a purpose-developed de-oxygenator module enabling the trans-wall oxygen distribution (high oxygen level at luminal side and low oxygen level at the adventitial side) existing in arterialized veins. Compared with standard cultures the bypass-specific conditions determined a significant increase in the proliferation of cells around adventitial vasa vasorum and an elevation in the length density of small and large caliber vasa vasorum. These results suggest, for the first time, a cause-effect relationship between the vein adventitial hypoxia and a neo-vascularization process, a factor known to predispose the arterialized vein conduits to restenosis.
Asunto(s)
Hipoxia/metabolismo , Oxígeno/metabolismo , Vena Safena/metabolismo , Vasa Vasorum/metabolismo , Femenino , Humanos , Hipoxia/patología , Hipoxia/fisiopatología , Masculino , Técnicas de Cultivo de Órganos , Vena Safena/patología , Vena Safena/fisiopatología , Vasa Vasorum/patología , Vasa Vasorum/fisiopatologíaRESUMEN
The aim of our study was to evaluate whether neo-vascularization of the carotid plaque can be accurately assessed by visual analysis of contrast-enhanced ultrasound images and whether these findings correlate with intensity-over-time curve analysis (ITC) and histopathology. Patients with ≥50% symptomatic or ≥60% asymptomatic stenosis according to European Carotid Surgery Trial criteria were included. Four investigators evaluated contrast enhancement visually (three grades), with positive agreement when three or more investigators were unanimous. ITC analysis of contrast enhancement was performed in the plaque and in the lumen. Histopathology (microvessel density with CD34 + staining) was completed when endarterectomy was performed. Visual grading (33 patients, inter-observer agreement = 94%) correlated significantly with ITC analysis (p = 0.03). Histopathology (n = 19) revealed a larger CD34 + area in patients with grade 1/2 versus grade 0 (p = 0.03). Visual analysis of neo-vascularization by means of contrast-enhanced ultrasound imaging is accurate and reproducible, with significant correlations with ITC and histopathology.