Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.381
Filtrar
1.
Cells ; 10(9)2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34571963

RESUMO

Stroke is the third leading cause of mortality in women and it kills twice as many women as breast cancer. A key role in the pathophysiology of stroke plays the disruption of the blood-brain barrier (BBB) within the neurovascular unit. While estrogen induces vascular protective actions, its influence on stroke remains unclear. Moreover, experiments assessing its impact on endothelial cells to induce barrier integrity are non-conclusive. Since pericytes play an active role in regulating BBB integrity and function, we hypothesize that estradiol may influence BBB by regulating their activity. In this study using human brain vascular pericytes (HBVPs) we investigated the impact of estradiol on key pericyte functions known to influence BBB integrity. HBVPs expressed estrogen receptors (ER-α, ER-ß and GPER) and treatment with estradiol (10 nM) inhibited basal cell migration but not proliferation. Since pericyte migration is a hallmark for BBB disruption following injury, infection and inflammation, we investigated the effects of estradiol on TNFα-induced PC migration. Importantly, estradiol prevented TNFα-induced pericyte migration and this effect was mimicked by PPT (ER-α agonist) and DPN (ER-ß agonist), but not by G1 (GPR30 agonist). The modulatory effects of estradiol were abrogated by MPP and PHTPP, selective ER-α and ER-ß antagonists, respectively, confirming the role of ER-α and ER-ß in mediating the anti-migratory actions of estrogen. To delineate the intracellular mechanisms mediating the inhibitory actions of estradiol on PC migration, we investigated the role of AKT and MAPK activation. While estradiol consistently reduced the TNFα-induced MAPK and Akt phosphorylation, only the inhibition of MAPK, but not Akt, significantly abrogated the migratory actions of TNFα. In transendothelial electrical resistance measurements, estradiol induced barrier function (TEER) in human brain microvascular endothelial cells co-cultured with pericytes, but not in HBMECs cultured alone. Importantly, transcriptomics analysis of genes modulated by estradiol in pericytes showed downregulation of genes known to increase cell migration and upregulation of genes known to inhibit cell migration. Taken together, our findings provide the first evidence that estradiol modulates pericyte activity and thereby improves endothelial integrity.


Assuntos
Encéfalo/irrigação sanguínea , Movimento Celular/efeitos dos fármacos , Estradiol/farmacologia , Perfilação da Expressão Gênica , Pericitos/citologia , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Pericitos/efeitos dos fármacos , Pericitos/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
2.
Int J Mol Sci ; 22(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445647

RESUMO

Unveiling the molecular features in the heart is essential for the study of heart diseases. Non-cardiomyocytes (nonCMs) play critical roles in providing structural and mechanical support to the working myocardium. There is an increasing amount of single-cell RNA-sequencing (scRNA-seq) data characterizing the transcriptomic profiles of nonCM cells. However, no tool allows researchers to easily access the information. Thus, in this study, we develop an open-access web portal, ExpressHeart, to visualize scRNA-seq data of nonCMs from five laboratories encompassing three species. ExpressHeart enables comprehensive visualization of major cell types and subtypes in each study; visualizes gene expression in each cell type/subtype in various ways; and facilitates identifying cell-type-specific and species-specific marker genes. ExpressHeart also provides an interface to directly combine information across datasets, for example, generating lists of high confidence DEGs by taking the intersection across different datasets. Moreover, ExpressHeart performs comparisons across datasets. We show that some homolog genes (e.g., Mmp14 in mice and mmp14b in zebrafish) are expressed in different cell types between mice and zebrafish, suggesting different functions across species. We expect ExpressHeart to serve as a valuable portal for investigators, shedding light on the roles of genes on heart development in nonCM cells.


Assuntos
Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Ventrículos do Coração/metabolismo , Internet , Macrófagos/metabolismo , Pericitos/metabolismo , Transcriptoma , Algoritmos , Animais , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Software , Peixe-Zebra
3.
Nat Biomed Eng ; 5(8): 847-863, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34385693

RESUMO

The therapeutic efficacy of stem cells transplanted into an ischaemic brain depends primarily on the responses of the neurovascular unit. Here, we report the development and applicability of a functional neurovascular unit on a microfluidic chip as a microphysiological model of ischaemic stroke that recapitulates the function of the blood-brain barrier as well as interactions between therapeutic stem cells and host cells (human brain microvascular endothelial cells, pericytes, astrocytes, microglia and neurons). We used the model to track the infiltration of a number of candidate stem cells and to characterize the expression levels of genes associated with post-stroke pathologies. We observed that each type of stem cell showed unique neurorestorative effects, primarily by supporting endogenous recovery rather than through direct cell replacement, and that the recovery of synaptic activities is correlated with the recovery of the structural and functional integrity of the neurovascular unit rather than with the regeneration of neurons.


Assuntos
AVC Isquêmico/terapia , Dispositivos Lab-On-A-Chip , Transplante de Células-Tronco , Astrócitos/citologia , Astrócitos/metabolismo , Barreira Hematoencefálica/química , Barreira Hematoencefálica/metabolismo , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Microglia/citologia , Microglia/metabolismo , Microvasos/citologia , Modelos Biológicos , Neurônios/citologia , Neurônios/metabolismo , Pericitos/citologia , Pericitos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
4.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445338

RESUMO

Recently, another new cell type was found in the perivascular space called a novel desmin-immunopositive perivascular (DIP) cell. However, the differences between this novel cell type and other nonhormone-producing cells have not been clarified. Therefore, we introduced several microscopic techniques to gain insight into the morphological characteristics of this novel DIP cell. We succeeded in identifying novel DIP cells under light microscopy using desmin immunocryosection, combining resin embedding blocks and immunoelectron microscopy. In conventional transmission electron microscopy, folliculostellate cells, capsular fibroblasts, macrophages, and pericytes presented a flat cisternae of rough endoplasmic reticulum, whereas those of novel DIP cells had a dilated pattern. The number of novel DIP cells was greatest in the intact rats, though nearly disappeared under prolactinoma conditions. Additionally, focused ion beam scanning electron microscopy showed that these novel DIP cells had multidirectional processes and some processes reached the capillary, but these processes did not tightly wrap the vessel, as is the case with pericytes. Interestingly, we found that the rough endoplasmic reticulum was globular and dispersed throughout the cytoplasmic processes after three-dimensional reconstruction. This study clearly confirms that novel DIP cells are a new cell type in the rat anterior pituitary gland, with unique characteristics.


Assuntos
Desmina/metabolismo , Pericitos , Adeno-Hipófise/diagnóstico por imagem , Animais , Desmina/análise , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Pericitos/citologia , Pericitos/metabolismo , Adeno-Hipófise/citologia , Adeno-Hipófise/metabolismo , Ratos , Ratos Wistar
5.
Nat Biomed Eng ; 5(8): 830-846, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34127820

RESUMO

The neurovascular unit, which consists of vascular cells surrounded by astrocytic end-feet and neurons, controls cerebral blood flow and the permeability of the blood-brain barrier (BBB) to maintain homeostasis in the neuronal milieu. Studying how some pathogens and drugs can penetrate the human BBB and disrupt neuronal homeostasis requires in vitro microphysiological models of the neurovascular unit. Here we show that the neurotropism of Cryptococcus neoformans-the most common pathogen causing fungal meningitis-and its ability to penetrate the BBB can be modelled by the co-culture of human neural stem cells, brain microvascular endothelial cells and brain vascular pericytes in a human-neurovascular-unit-on-a-chip maintained by a stepwise gravity-driven unidirectional flow and recapitulating the structural and functional features of the BBB. We found that the pathogen forms clusters of cells that penetrate the BBB without altering tight junctions, suggesting a transcytosis-mediated mechanism. The neurovascular-unit-on-a-chip may facilitate the study of the mechanisms of brain infection by pathogens, and the development of drugs for a range of brain diseases.


Assuntos
Barreira Hematoencefálica/metabolismo , Cryptococcus neoformans/fisiologia , Dispositivos Lab-On-A-Chip , Modelos Biológicos , Barreira Hematoencefálica/química , Barreira Hematoencefálica/microbiologia , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Matriz Extracelular/química , Humanos , Hidrogéis/química , Meningite/microbiologia , Meningite/patologia , Microvasos/citologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Pericitos/citologia , Pericitos/metabolismo , Transcitose
6.
Am J Physiol Heart Circ Physiol ; 320(6): H2438-H2447, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33961504

RESUMO

Adventitial abnormalities including enhanced vasa vasorum malformation are associated with development and vulnerability of atherosclerotic plaque. However, the mechanisms of vasa vasorum malformation and its role in vascular remodeling have not been fully clarified. We recently reported that ninjurin-1 (Ninj1) is a crucial adhesion molecule for pericytes to form matured neovessels. The purpose is to examine if Ninj1 regulates adventitial angiogenesis and affects the vascular remodeling of injured vessels using pericyte-specific Ninj1 deletion mouse model. Mouse femoral arteries were injured by insertion of coiled wire. Four weeks after vascular injury, fixed arteries were decolorized. Vascular remodeling, including intimal hyperplasia and adventitial microvessel formation were estimated in a three-dimensional view. Vascular fragility, including blood leakiness was estimated by extravasation of fluorescein isothiocyanate (FITC)-lectin or FITC-dextran from microvessels. Ninj1 expression was increased in pericytes in response to vascular injury. NG2-CreER/Ninj1loxp mice were treated with tamoxifen (Tam) to induce deletion of Ninj1 in pericyte (Ninj1 KO). Tam-treated NG2-CreER or Tam-nontreated NG2-CreER/Ninj1loxp mice were used as controls. Intimal hyperplasia was significantly enhanced in Ninj1 KO compared with controls. Vascular leakiness was significantly enhanced in Ninj1 KO. In Ninj1 KO, the number of infiltrated macrophages in adventitia was increased, along with the expression of inflammatory cytokines. In conclusion, deletion of Ninj1 in pericytes induces the immature vasa vasorum formation of injured vasculature and exacerbates adventitial inflammation and intimal hyperplasia. Thus, Ninj1 contributes to the vasa vasorum maturation in response to vascular injury and to reduction of vascular remodeling.NEW & NOTEWORTHY Although abnormalities of adventitial vasa vasorum are associated with vascular remodeling such as atherosclerosis, the mechanisms of vasa vasorum malformation and its role in vascular remodeling have not been fully clarified. The present study provides a line of novel evidence that ninjurin-1 contributes to adventitial microvascular maturation during vascular injury and regulates vascular remodeling.


Assuntos
Moléculas de Adesão Celular Neuronais/genética , Artéria Femoral/metabolismo , Neointima/genética , Fatores de Crescimento Neural/genética , Pericitos/metabolismo , Vasa Vasorum/metabolismo , Remodelação Vascular/genética , Túnica Adventícia/metabolismo , Túnica Adventícia/patologia , Animais , Artéria Femoral/lesões , Artéria Femoral/patologia , Técnicas de Inativação de Genes , Hiperplasia/genética , Inflamação/genética , Inflamação/metabolismo , Macrófagos/patologia , Camundongos , Neointima/patologia , Neovascularização Fisiológica/genética , Transcriptoma , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Vasa Vasorum/patologia , Lesões do Sistema Vascular/genética , Lesões do Sistema Vascular/metabolismo , Lesões do Sistema Vascular/patologia
7.
Diabetes ; 70(8): 1738-1753, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33975909

RESUMO

The current understanding of the molecular pathogenesis of diabetic retinopathy does not provide a mechanistic link between early molecular changes and the subsequent progression of the disease. In this study, we found that human diabetic retinas overexpressed TRIB3 and investigated the role of TRIB3 in diabetic retinal pathobiology in mice. We discovered that TRIB3 controlled major molecular events in early diabetic retinas via HIF1α-mediated regulation of retinal glucose flux, reprogramming cellular metabolism, and governing of inflammatory gene expression. These early molecular events further defined the development of neurovascular deficit observed in mice with diabetic retinopathy. TRIB3 ablation in the streptozotocin-induced mouse model led to significant retinal ganglion cell survival and functional restoration accompanied by a dramatic reduction in pericyte loss and acellular capillary formation. Under hypoxic conditions, TRIB3 contributed to advanced proliferative stages by significant upregulation of GFAP and VEGF expression, thus controlling gliosis and aberrant vascularization in oxygen-induced retinopathy mouse retinas. Overall, our data reveal that TRIB3 is a master regulator of diabetic retinal pathophysiology that may accelerate the onset and progression of diabetic retinopathy to proliferative stages in humans and present TRIB3 as a potentially novel therapeutic target for diabetic retinopathy.


Assuntos
Proteínas de Ciclo Celular/genética , Retinopatia Diabética/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Repressoras/genética , Retina/metabolismo , Animais , Capilares/metabolismo , Capilares/patologia , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Progressão da Doença , Humanos , Camundongos , Pericitos/metabolismo , Pericitos/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Retina/patologia
8.
J Cereb Blood Flow Metab ; 41(8): 1873-1885, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33853406

RESUMO

Local blood flow in the brain is tightly coupled to metabolic demands, a phenomenon termed functional hyperemia. Both capillaries and arterioles contribute to the hyperemic response to neuronal activity via different mechanisms and timescales. The nature and specific signaling involved in the hyperemic response of capillaries versus arterioles, and their temporal relationship are not fully defined. We determined the time-dependent changes in capillary flux and diameter versus arteriolar velocity and flow following whisker stimulation using optical microangiography (OMAG) and two-photon microscopy. We further characterized depth-resolved responses of individual capillaries versus capillary networks. We hypothesized that capillaries respond first to neuronal activation, and that they exhibit a coordinated response mediated via endothelial-derived epoxyeicosatrienoates (EETs) acting on pericytes. To visualize peri-capillary pericytes, we used Tie2-GFP/NG2-DsRed mice, and to determine the role of endothelial-derived EETs, we compared cerebrovascular responses to whisker stimulation between wild-type mice and mice with lower endothelial EETs (Tie2-hsEH). We found that capillaries respond immediately to neuronal activation in an orchestrated network-level manner, a response attenuated in Tie2-hsEH and inhibited by blocking EETs action on pericytes. These results demonstrate that capillaries are first responders during functional hyperemia, and that they exhibit a network-level response mediated via endothelial-derived EETs' action on peri-capillary pericytes.


Assuntos
Capilares/fisiologia , Endotélio/metabolismo , Neurônios/fisiologia , Pericitos/metabolismo , Fluxo Sanguíneo Regional/fisiologia , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Ácido 8,11,14-Eicosatrienoico/farmacologia , Animais , Arteríolas/fisiologia , Capilares/efeitos dos fármacos , Estimulação Elétrica , Epóxido Hidrolases/metabolismo , Hiperemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência por Excitação Multifotônica , Tomografia de Coerência Óptica , Vasoconstrição/efeitos dos fármacos
9.
Int J Mol Sci ; 22(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925714

RESUMO

A pericyte-like differentiation of human adipose-derived mesenchymal stem cells (ASCs) was tested in in vitro experiments for possible therapeutic applications in cases of diabetic retinopathy (DR) to replace irreversibly lost pericytes. For this purpose, pericyte-like ASCs were obtained after their growth in a specific pericyte medium. They were then cultured in high glucose conditions to mimic the altered microenvironment of a diabetic eye. Several parameters were monitored, especially those particularly affected by disease progression: cell proliferation, viability and migration ability; reactive oxygen species (ROS) production; inflammation-related cytokines and angiogenic factors. Overall, encouraging results were obtained. In fact, even after glucose addition, ASCs pre-cultured in the pericyte medium (pmASCs) showed high proliferation rate, viability and migration ability. A considerable increase in mRNA expression levels of the anti-inflammatory cytokines transforming growth factor-ß1 (TGF-ß1) and interleukin-10 (IL-10) was observed, associated with reduction in ROS production, and mRNA expression of pro-inflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), and angiogenic factors. Finally, a pmASC-induced better organization of tube-like formation by retinal endothelial cells was observed in three-dimensional co-culture. The pericyte-like ASCs obtained in these experiments represent a valuable tool for the treatment of retinal damages occurring in diabetic patients.


Assuntos
Glucose/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Pericitos/metabolismo , Tecido Adiposo/metabolismo , Adulto , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Retinopatia Diabética/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Itália , Células-Tronco Mesenquimais/metabolismo , Retina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
10.
Oxid Med Cell Longev ; 2021: 8833098, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815662

RESUMO

Diabetic retinopathy (DR) is a frequently occurring microvascular complication induced by long-term hyperglycemia. Pericyte-endothelial cell crosstalk is critical for maintaining vascular homeostasis and remodeling; however, the molecular mechanism underlying that crosstalk remains unknown. In this study, we explored the crosstalk that occurs between endothelial cells and pericytes in response to diabetic retinopathy. Pericytes were stimulated with cobalt chloride (CoCl2) to activate the HIF pathway. Hypoxia-stimulated pericytes were cocultured with high glucose- (HG-) induced endotheliocytes. Cell viability was determined using the CCK-8 assay. Western blot studies were performed to detect the expression of proteins associated with apoptosis, hypoxia, and inflammation. ELISA assays were conducted to analyze the release of IL-1ß and IL-18. We performed a circRNA microarray analysis of exosomal RNAs expressed under normoxic or hypoxic conditions. A FISH assay was performed to identify the location of circEhmt1 in pericytes. Chromatin immunoprecipitation (CHIP) was used to identify the specific DNA-binding site on the NFIA-NLRP3 complex. We found that pericyte survival was negatively correlated with the angiogenesis activity of endotheliocytes. We also found that hypoxia upregulated circEhmt1 expression in pericytes, and circEhmt1 could be transferred from pericytes to endotheliocytes via exosomes. Moreover, circEhmt1 overexpression protected endotheliocytes against HG-induced injury in vitro. Mechanistically, circEhmt1 was highly expressed in the nucleus of pericytes and could upregulate the levels of NFIA (a transcription factor) to suppress NLRP3-mediated inflammasome formation. Our study revealed a critical role for circEhmt1-mediated NFIA/NLRP3 signaling in retinal microvascular dysfunction and suggests that signaling pathway as a target for treating DR.


Assuntos
Exossomos/metabolismo , Glucose/toxicidade , Microvasos/fisiopatologia , Fatores de Transcrição NFI/metabolismo , Pericitos/metabolismo , RNA Circular/metabolismo , Transdução de Sinais , Animais , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Exossomos/efeitos dos fármacos , Camundongos , Microvasos/efeitos dos fármacos , Microvasos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Pericitos/efeitos dos fármacos , Substâncias Protetoras/metabolismo , RNA Circular/genética , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
11.
Biochem Biophys Res Commun ; 552: 37-43, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33740663

RESUMO

Ghrelin is a peptide hormone with strong anti-inflammatory properties. In fact, Ghrelin was reported to improve endothelial dysfunction caused by excessive fat. However, its role in preserving the integrity of brain microvascular, under conditions of lipid dysregulation and inflammation, is not known. The objective of this study is to characterize the role of Ghrelin in the protection of cerebral microvascular integrity, during atherosclerosis, and uncover its underlying molecular mechanism. Our results demonstrated that an atherosclerotic condition, brought on by a high fat diet (HFD), can produce massive increases in serum inflammatory factors, blood lipids, cerebral microvascular leakage, and activation of the p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) (p38 MAPK-JNK) pathway. It also produced significantly damaged pericytes morphology, resulting in pericyte decrease. Ghrelin treatment, on the other hand, protected against cerebral microvascular leakage and pericytes damage. Ghrelin effectively downregulated the expression of pro-inflammatory cytokines, and it also suppressed the p38 MAPK-JNK signaling pathway. Additionally, in isolated mouse cerebral microvascular pericytes, ox-LDL lead to increased apoptosis and secretion of inflammatory factors, along with an elevation in phosphorylated p38 MAPK-JNK proteins. Alternately, Ghrelin administration markedly lowered expression of inflammatory factors, suppressed the p38 MAPK-JNK signaling path, and halted cell apoptosis. However, pretreatment of Hesperetin, a p38 MAPK-JNK agonist, abrogated the Ghrelin-mediated suppression of inflammation and apoptosis in pericytes. Taken together, these results suggest that Ghrelin restored cerebral microvascular integrity and reduced vascular leakage in atherosclerosis mice, in part, by its regulation of inflammatory and apoptotic signaling pathways in pericytes.


Assuntos
Apoptose/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Grelina/farmacologia , Inflamação/prevenção & controle , MAP Quinase Quinase 4/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Aterosclerose/metabolismo , Aterosclerose/fisiopatologia , Aterosclerose/prevenção & controle , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Grelina/administração & dosagem , Inflamação/metabolismo , Inflamação/fisiopatologia , Injeções Intraperitoneais , Lipoproteínas LDL/antagonistas & inibidores , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Masculino , Camundongos Knockout , Pericitos/citologia , Pericitos/efeitos dos fármacos , Pericitos/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Int J Biochem Cell Biol ; 134: 105971, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33775914

RESUMO

Pericytes (PC) are microvascular mural cells that make specific cell-to-cell contacts with the endothelial cells (EC). These cells are obligatory constituents of the microvessels including the retinal vasculature and they serve as regulators of vascular development, stabilization, maturation and remodeling. During early stages of diabetic retinopathy (DR), apoptotic loss of PC surrounding the retinal vasculature occurs. This may lead to reduced vessel stability, the onset of EC apoptosis, and subsequent retinal ischemia leading to angiogenesis and eventually, severe vision loss due to late proliferative diabetic retinopathy (PDR). Similarly, diabetic nephropathy (DN) is a chronic kidney disease due to hyperglycemia that particularly affects renal PC. Chronic high blood glucose level causes migration of peritubular PC away from the capillary into the interstitial space, which destabilizes the micro vessels, resulting in microvascular rarefaction. In both diabetes associated complications, the identification of specific biomarkers is necessary to stabilize the PC at an early stage. This review largely covers the importance of PC towards the pathogenesis of diabetes associated complications, and their heterogeneity in healthy and angiogenic vasculature.


Assuntos
Diabetes Mellitus/fisiopatologia , Nefropatias Diabéticas/patologia , Retinopatia Diabética/patologia , Células Endoteliais/patologia , Microvasos/patologia , Neovascularização Patológica/patologia , Pericitos/patologia , Animais , Apoptose/fisiologia , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/metabolismo , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Humanos , Microvasos/metabolismo , Pericitos/metabolismo
13.
Cancer Res ; 81(8): 2142-2156, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593822

RESUMO

The extraordinary plasticity of glioma cells allows them to contribute to different cellular compartments in tumor vessels, reinforcing the vascular architecture. It was recently revealed that targeting glioma-derived pericytes, which represent a big percentage of the mural cell population in aggressive tumors, increases the permeability of the vessels and improves the efficiency of chemotherapy. However, the molecular determinants of this transdifferentiation process have not been elucidated. Here we show that mutations in EGFR stimulate the capacity of glioma cells to function as pericytes in a BMX- (bone marrow and X-linked) and SOX9-dependent manner. Subsequent activation of platelet-derived growth factor receptor beta in the vessel walls of EGFR-mutant gliomas stabilized the vasculature and facilitated the recruitment of immune cells. These changes in the tumor microenvironment conferred a growth advantage to the tumors but also rendered them sensitive to pericyte-targeting molecules such as ibrutinib or sunitinib. In the absence of EGFR mutations, high-grade gliomas were enriched in blood vessels, but showed a highly disrupted blood-brain barrier due to the decreased BMX/SOX9 activation and pericyte coverage, which led to poor oxygenation, necrosis, and hypoxia. Overall, these findings identify EGFR mutations as key regulators of the glioma-to-pericyte transdifferentiation, highlighting the intricate relationship between the tumor cells and their vascular and immune milieu. Our results lay the foundations for a vascular-dependent stratification of gliomas and suggest different therapeutic vulnerabilities determined by the genetic status of EGFR. SIGNIFICANCE: This study identifies the EGFR-related mechanisms that govern the capacity of glioma cells to transdifferentiate into pericytes, regulating the vascular and immune phenotypes of the tumors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/8/2142/F1.large.jpg.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Transdiferenciação Celular , Microambiente Celular , Glioma/irrigação sanguínea , Mutação , Pericitos/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Barreira Hematoencefálica/metabolismo , Medula Óssea , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Cromossomos Humanos X , Receptores ErbB/genética , Glioma/imunologia , Glioma/patologia , Humanos , Imunidade Celular , Isocitrato Desidrogenase/genética , Camundongos , Pericitos/efeitos dos fármacos , Pericitos/metabolismo , Piperidinas/farmacologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Transcrição SOX9 , Sunitinibe/farmacologia , Hipóxia Tumoral , Microambiente Tumoral
14.
Commun Biol ; 4(1): 260, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637884

RESUMO

Neuroinflammation is a key component of virtually all neurodegenerative diseases, preceding neuronal loss and associating directly with cognitive impairment. Neuroinflammatory signals can originate and be amplified at barrier tissues such as brain vasculature, surrounding meninges and the choroid plexus. We designed a high content screening system to target inflammation in human brain-derived cells of the blood-brain barrier (pericytes and endothelial cells) to identify inflammatory modifiers. Screening an FDA-approved drug library we identify digoxin and lanatoside C, members of the cardiac glycoside family, as inflammatory-modulating drugs that work in blood-brain barrier cells. An ex vivo assay of leptomeningeal and choroid plexus explants confirm that these drugs maintain their function in 3D cultures of brain border tissues. These results suggest that cardiac glycosides may be useful in targeting inflammation at border regions of the brain and offer new options for drug discovery approaches for neuroinflammatory driven degeneration.


Assuntos
Anti-Inflamatórios/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Plexo Corióideo/efeitos dos fármacos , Digoxina/farmacologia , Células Endoteliais/efeitos dos fármacos , Inflamação/tratamento farmacológico , Lanatosídeos/farmacologia , Meninges/efeitos dos fármacos , Pericitos/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Células Cultivadas , Plexo Corióideo/metabolismo , Plexo Corióideo/patologia , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Ensaios de Triagem em Larga Escala , Humanos , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Meninges/metabolismo , Meninges/patologia , Pericitos/metabolismo , Pericitos/patologia , Técnicas de Cultura de Tecidos
15.
Diab Vasc Dis Res ; 18(1): 1479164121990641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33557613

RESUMO

AIM: Diabetes-related cerebral small vessel disease (CSVD) causes neurological deficits. Patients with diabetes showed pericyte loss as a hallmark of retinopathy. Cerebral pericytes, which densely localize around brain capillaries, are quiescent stem cells regulating regeneration of brain and may have a role in CSVD development. This study investigated whether diabetes impairs ischemia-provoked dedifferentiation of pericytes. METHODS: A murine high-fat diet (HFD)-induced diabetes model was used. After cerebral ischemia induction in the mice, pericytes were isolated and grown for a sphere formation assay. RESULTS: The sphere counts from the HFD group were lower than those in the chow group. As the spheres formed, pericyte marker levels decreased and SOX2 levels increased gradually in the chow group, but not in the HFD group. Before sphere formation, pericytes from the HFD group showed high p21 levels. The use of a p21 inhibitor rescued the reduction of sphere counts in the HFD group. At cellular level, hyperglycemia-induced ROS increased the level of p21 in cerebral pericytes. The p21-SOX2 signaling was then activated after oxygen-glucose deprivation. CONCLUSION: HFD-induced diabetes compromises the stemness of cerebral pericytes by altering p21-SOX2 signaling. These results provide evidence supporting the role of pericytes in diabetes-related CSVD and subsequent cerebral dysfunction.


Assuntos
Glicemia/metabolismo , Desdiferenciação Celular , Doenças de Pequenos Vasos Cerebrais/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Diabetes Mellitus/sangue , Infarto da Artéria Cerebral Média/metabolismo , Pericitos/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Animais , Biomarcadores/sangue , Hipóxia Celular , Células Cultivadas , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/patologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Masculino , Camundongos Endogâmicos C57BL , Pericitos/patologia , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
17.
Int J Mol Sci ; 22(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562136

RESUMO

Nanoparticle (NP)-assisted procedures including laser tissue soldering (LTS) offer advantages compared to conventional microsuturing, especially in the brain. In this study, effects of polymer-coated silica NPs used in LTS were investigated in human brain endothelial cells (ECs) and blood-brain barrier models. In the co-culture setting with ECs and pericytes, only the cell type directly exposed to NPs displayed a time-dependent internalization. No transfer of NPs between the two cell types was observed. Cell viability was decreased relatively to NP exposure duration and concentration. Protein expression of the nuclear factor ĸ-light-chain-enhancer of activated B cells and various endothelial adhesion molecules indicated no initiation of inflammation or activation of ECs after NP exposure. Differentiation of CD34+ ECs into brain-like ECs co-cultured with pericytes, blood-brain barrier (BBB) characteristics were obtained. The established endothelial layer reduced the passage of integrity tracer molecules. NP exposure did not result in alterations of junctional proteins, BBB formation or its integrity. In a 3-dimensional setup with an endothelial tube formation and tight junctions, barrier formation was not disrupted by the NPs and NPs do not seem to cross the blood-brain barrier. Our findings suggest that these polymer-coated silica NPs do not damage the BBB.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Revascularização Cerebral/métodos , Células Endoteliais/metabolismo , Nanopartículas/metabolismo , Polímeros/farmacologia , Dióxido de Silício/farmacologia , Animais , Linfócitos B/imunologia , Transporte Biológico/fisiologia , Barreira Hematoencefálica/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/metabolismo , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Terapia a Laser/métodos , Ativação Linfocitária/imunologia , NF-kappa B/metabolismo , Pericitos/metabolismo
18.
Methods Mol Biol ; 2235: 13-26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33576967

RESUMO

The physiological, pathological, and regenerative roles of pericytes as microvascular mural cells and multipotent precursors have gained significant attention. The capacity to prospectively purify pericytes from multiple organs enables the investigation of their tissue-specific regenerative capabilities. Here, we describe the application of purified human pericytes for cardiac regeneration post-infarct in an immunodeficient mouse model. This protocol includes experimental details of pericyte isolation from both human skeletal and cardiac muscle, an immunodeficient mouse model of acute myocardial infarction, and xenogeneic pericyte transplantation.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Pericitos/transplante , Regeneração/fisiologia , Animais , Humanos , Masculino , Camundongos , Camundongos SCID , Miocárdio/patologia , Neovascularização Fisiológica , Pericitos/metabolismo
19.
Methods Mol Biol ; 2235: 27-35, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33576968

RESUMO

Pericytes are mural cells closely associated with endothelial cells in capillaries and microvessels. They are precursors of mesenchymal stem/stromal cells that have historically been retrospectively characterized in culture. We established a protocol, described in this chapter, to characterize and isolate pericytes from multiple human organs by flow cytometry and fluorescence-activated cell sorting. This prospective purification of pericytes brings us a step forward in the development of strategies for their use in the clinic.


Assuntos
Citometria de Fluxo/métodos , Pericitos/citologia , Pericitos/transplante , Capilares/citologia , Técnicas de Cultura de Células/métodos , Separação Celular/métodos , Células Cultivadas , Células Endoteliais/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Microvasos/citologia , Pericitos/metabolismo , Fenótipo
20.
Methods Mol Biol ; 2235: 37-45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33576969

RESUMO

Pericytes are found in all vascularized organs and are defined anatomically as perivascular cells that closely surround endothelial cells in capillaries and microvessels and are embedded within the same basement membrane. They have been shown to have diverse physiological and pathological functions including regulation of blood pressure, and tissue regeneration and scarring. Fundamental to understanding the role these cells play in these diverse processes is the ability to accurately identify and localize them in vivo. To do this, we have developed multicolor immunohistochemistry protocols described in this chapter.


Assuntos
Imuno-Histoquímica/métodos , Pericitos/citologia , Pericitos/transplante , Capilares/citologia , Diferenciação Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/citologia , Humanos , Microvasos/citologia , Pericitos/metabolismo , Fenótipo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...