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1.
Int J Mol Sci ; 22(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34769052

RESUMO

A wide range of neurological manifestations have been associated with the development of COVID-19 following SARS-CoV-2 infection. However, the etiology of the neurological symptomatology is still largely unexplored. Here, we used state-of-the-art multiplexed immunostaining of human brains (n = 6 COVID-19, median age = 69.5 years; n = 7 control, median age = 68 years) and demonstrated that expression of the SARS-CoV-2 receptor ACE2 is restricted to a subset of neurovascular pericytes. Strikingly, neurological symptoms were exclusive to, and ubiquitous in, patients that exhibited moderate to high ACE2 expression in perivascular cells. Viral dsRNA was identified in the vascular wall and paralleled by perivascular inflammation, as signified by T cell and macrophage infiltration. Furthermore, fibrinogen leakage indicated compromised integrity of the blood-brain barrier. Notably, cerebrospinal fluid from additional 16 individuals (n = 8 COVID-19, median age = 67 years; n = 8 control, median age = 69.5 years) exhibited significantly lower levels of the pericyte marker PDGFRß in SARS-CoV-2-infected cases, indicative of disrupted pericyte homeostasis. We conclude that pericyte infection by SARS-CoV-2 underlies virus entry into the privileged central nervous system space, as well as neurological symptomatology due to perivascular inflammation and a locally compromised blood-brain barrier.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Encéfalo/virologia , COVID-19/fisiopatologia , Encefalite Viral/virologia , Pericitos/virologia , Enzima de Conversão de Angiotensina 2/genética , Animais , Barreira Hematoencefálica , Encéfalo/patologia , COVID-19/etiologia , Estudos de Casos e Controles , Encefalite Viral/patologia , Fibrinogênio/metabolismo , Humanos , Imuno-Histoquímica/métodos , Camundongos , Pericitos/metabolismo , Pericitos/patologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/líquido cefalorraquidiano
3.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 56(11): 1185-1193, 2021 Nov 07.
Artigo em Chinês | MEDLINE | ID: mdl-34749458

RESUMO

Objective: To study the changes in the permeability of the blood labyrinth barrier of the aging cochlea in mice, and to establish a non-contact co-culture model of endothelial cells (EC) and pericytes (PC) to furtherly investigate the cochlear stria vascularis microvascular pericytes impact on the permeability of endothelial cells. Methods: C57BL/6J mice were divided into two groups, three months old as young group, 12 months old as senile group. Cell experiment was divided into four groups, EC group, EC+PC co-culture group, D-gal+EC group and D-gal+EC+PC co-culture group. Auditory brainstem response (auditory brain response, ABR) was used to detect the auditory function of the two groups of mice. Evans blue staining was applied to detect the permeability of the cochlear blood labyrinth barrier of the two groups of mice. Transmission electron microscopy was used to observe the ultrastructure of blood labyrinth barrier endothelial cells, pericytes and tight junctions in the two groups of mice. Immunohistochemistry was used to detect the expression levels of tight junction proteins in the stria vascularis of the cochlea of the two groups of mice. Transwell chamber was used to detect the permeability of endothelial cells. Western blot and immunofluorescence technology were used to detect the expression level of tight junction protein on endothelial cells. SPSS 20.0 software was used to analyze the data. Results: Compared with the young group, the ABR threshold of the aging group was significantly increased, the latency of wave I was prolonged (t=10.25, P<0.01;t=5.61, P<0.05), the permeability of the cochlear blood labyrinth barrier was increased and the expression of tight junction protein on the vascular stria was decreased (P<0.05). The cochlear ultrastructure showed that the cochlear vascular stria microvascular lumen was deformed, the basement membrane thickened and the tight junction gap between endothelium enlarged. The positive rate of ECs and PCs in primary culture was more than 95%. The cells induced by 15 g/L D-gal were determined to be senescent cells. Compared with EC group, the expression of tight junction protein in endothelial cells of D-gal+EC group decreased(t=7.42,P<0.01;t=13.19,P<0.05)and the permeability increased (t=11.17, P<0.01). In the co-culture group, the expression of tight junction protein between endothelial cells in EC+PC co-culture group and D-gal+EC+PC co-culture group increased and the permeability decreased. Conclusions: In aging mice, the permeability of cochlear blood labyrinth barrier will increase and the level of tight junction protein will decrease; in aging state, cochlear vascular stria microvascular pericytes may affect endothelial cell permeability by regulating the expression of tight junction protein.


Assuntos
Pericitos , Estria Vascular , Animais , Cóclea , Células Endoteliais , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade , Junções Íntimas
4.
Adv Exp Med Biol ; 1329: 253-269, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34664244

RESUMO

Thyroid cancer is the most common endocrine malignancy, and aggressive radioactive iodine refractory thyroid carcinomas still lack an effective treatment. A deeper understanding of tumor heterogeneity and microenvironment will be critical to establishing new therapeutic approaches. One of the important influencing factors of tumor heterogeneity is the diversity of cells in the tumor microenvironment. Among these are pericytes, which play an important role in blood vessel stability and angiogenesis, as well as tumor growth and metastasis. Pericytes also have stem cell-like properties and are a heterogeneous cell population, and their lineage, which has been challenging to define, may impact tumor resistance at different tumor stages. Pericytes are also important stroma cell types in the angiogenic microenvironment which express tyrosine-kinase (TK) pathways (e.g., PDGFR-ß). Although TK inhibitors (TKI) and BRAFV600E inhibitors are currently used in the clinic for thyroid cancer, their efficacy is not durable and drug resistance often develops. Characterizing the range of distinct pericyte populations and distinguishing them from other perivascular cell types may enable the identification of their specific functions in the thyroid carcinoma vasculature. This remains an essential step in developing new therapeutic strategies. Also, assessing whether thyroid tumors hold immature and/or mature vasculature with pericyte populations coverage may be key to predicting tumor response to either targeted or anti-angiogenesis therapies. It is also critical to apply different markers in order to identify pericyte populations and characterize their cell lineage. This chapter provides an overview of pericyte ontogenesis and the lineages of diverse cell populations. We also discuss the role(s) and targeting of pericytes in thyroid carcinoma, as well as their potential impact on precision targeted therapies and drug resistance.


Assuntos
Pericitos , Neoplasias da Glândula Tireoide , Humanos , Radioisótopos do Iodo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Microambiente Tumoral
5.
Nat Commun ; 12(1): 5907, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625559

RESUMO

Parkinson's disease and related synucleinopathies are characterized by the abnormal accumulation of alpha-synuclein aggregates, loss of dopaminergic neurons, and gliosis of the substantia nigra. Although clinical evidence and in vitro studies indicate disruption of the Blood-Brain Barrier in Parkinson's disease, the mechanisms mediating the endothelial dysfunction is not well understood. Here we leveraged the Organs-on-Chips technology to develop a human Brain-Chip representative of the substantia nigra area of the brain containing dopaminergic neurons, astrocytes, microglia, pericytes, and microvascular brain endothelial cells, cultured under fluid flow. Our αSyn fibril-induced model was capable of reproducing several key aspects of Parkinson's disease, including accumulation of phosphorylated αSyn (pSer129-αSyn), mitochondrial impairment, neuroinflammation, and compromised barrier function. This model may enable research into the dynamics of cell-cell interactions in human synucleinopathies and serve as a testing platform for target identification and validation of novel therapeutics.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Doença de Parkinson/metabolismo , Sinucleinopatias/metabolismo , alfa-Sinucleína/metabolismo , Astrócitos/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neurônios Dopaminérgicos/metabolismo , Células Endoteliais/metabolismo , Gliose/patologia , Humanos , Microglia/metabolismo , Mitocôndrias/metabolismo , Pericitos/metabolismo , Fosforilação , Substância Negra/metabolismo , Transcriptoma
6.
Ann Pathol ; 41(6): 561-566, 2021 Nov.
Artigo em Francês | MEDLINE | ID: mdl-34629216

RESUMO

Glomus tumor are rare mesenchymal neoplasm, belonging to the pericytic (perivascular) tumor family, witch recent molecular characterization has allowed highlight recurrent molecular abnormalities. In fact, glomus tumor involves frequent MIR143-NOTCH gene fusion whereas others pericytic tumor (myopericytoma and myofibroma) involve mutations of PDGFRB gene. Glomus tumor are usually developed in superficial localization. However visceral locations have been described. Cardiac location is exceptional with only one case reported in literature. Here, we report the case of cardiac glomus tumor (glomangiomyoma) developed in the left ventricle in a 34 year-old patient, diagnosed after chest pain. The length of tumor was 4cm in greatest dimension. Histologically, the tumor concerned both round glomus cells and smooth muscle cells with prominent branching thin-walled vessels. By immunohistochemistry, these two contingents exhibited diffuse expression of smooth muscle actin and heterogeneous expression of H-caldesmone whereas cytokeratins, melanocytic markers and chomogranine were negative. Next Generation molecular analysis using RNA sequencing highlighted the characteristic MIR143-NOTCH gene fusion witch supports the diagnosis of glomus tumor. In this observation, we recall histological and immunohistochemistry features of glomus tumor and we make a synthesis concerning the molecular data recently described in sporadic glomus tumor.


Assuntos
Tumor Glômico , MicroRNAs , Miofibroma , Adulto , Biomarcadores Tumorais , Tumor Glômico/diagnóstico , Tumor Glômico/cirurgia , Humanos , Imuno-Histoquímica , Pericitos
7.
Nat Commun ; 12(1): 6011, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650057

RESUMO

Defective pericyte-endothelial cell interaction in tumors leads to a chaotic, poorly organized and dysfunctional vasculature. However, the underlying mechanism behind this is poorly studied. Herein, we develop a method that combines magnetic beads and flow cytometry cell sorting to isolate pericytes from tumors and normal adjacent tissues from patients with non-small cell lung cancer (NSCLC) and hepatocellular carcinoma (HCC). Pericytes from tumors show defective blood vessel supporting functions when comparing to those obtained from normal tissues. Mechanistically, combined proteomics and metabolic flux analysis reveals elevated hexokinase 2(HK2)-driven glycolysis in tumor pericytes, which up-regulates their ROCK2-MLC2 mediated contractility leading to impaired blood vessel supporting function. Clinically, high percentage of HK2 positive pericytes in blood vessels correlates with poor patient overall survival in NSCLC and HCC. Administration of a HK2 inhibitor induces pericyte-MLC2 driven tumor vasculature remodeling leading to enhanced drug delivery and efficacy against tumor growth. Overall, these data suggest that glycolysis in tumor pericytes regulates their blood vessel supporting role.


Assuntos
Vasos Sanguíneos/anormalidades , Glicólise , Hexoquinase/metabolismo , Neoplasias de Tecido Vascular/metabolismo , Pericitos/metabolismo , Células A549 , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Miosinas Cardíacas/genética , Miosinas Cardíacas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Hexoquinase/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Cadeias Leves de Miosina/genética , Cadeias Leves de Miosina/metabolismo , Neoplasias/metabolismo , Neoplasias de Tecido Vascular/tratamento farmacológico , Neoplasias de Tecido Vascular/genética , Neoplasias de Tecido Vascular/patologia , Microambiente Tumoral/fisiologia , Regulação para Cima , Quinases Associadas a rho
8.
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
9.
Nat Commun ; 12(1): 5501, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535655

RESUMO

Fibrotic scar tissue limits central nervous system regeneration in adult mammals. The extent of fibrotic tissue generation and distribution of stromal cells across different lesions in the brain and spinal cord has not been systematically investigated in mice and humans. Furthermore, it is unknown whether scar-forming stromal cells have the same origin throughout the central nervous system and in different types of lesions. In the current study, we compared fibrotic scarring in human pathological tissue and corresponding mouse models of penetrating and non-penetrating spinal cord injury, traumatic brain injury, ischemic stroke, multiple sclerosis and glioblastoma. We show that the extent and distribution of stromal cells are specific to the type of lesion and, in most cases, similar between mice and humans. Employing in vivo lineage tracing, we report that in all mouse models that develop fibrotic tissue, the primary source of scar-forming fibroblasts is a discrete subset of perivascular cells, termed type A pericytes. Perivascular cells with a type A pericyte marker profile also exist in the human brain and spinal cord. We uncover type A pericyte-derived fibrosis as a conserved mechanism that may be explored as a therapeutic target to improve recovery after central nervous system lesions.


Assuntos
Sistema Nervoso Central/patologia , Cicatriz/patologia , Pericitos/patologia , Envelhecimento/fisiologia , Animais , Astrócitos/patologia , Lesões Encefálicas Traumáticas/patologia , Isquemia Encefálica/patologia , Neoplasias Encefálicas/patologia , Córtex Cerebral/patologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/patologia , Matriz Extracelular/metabolismo , Fibroblastos/patologia , Fibrose , Glioblastoma/patologia , Humanos , AVC Isquêmico/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Glicoproteína Mielina-Oligodendrócito , Fragmentos de Peptídeos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Medula Espinal/patologia , Medula Espinal/ultraestrutura , Traumatismos da Medula Espinal/patologia , Células Estromais/patologia
10.
Cells ; 10(9)2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34571892

RESUMO

An important objective of vascularized tissue regeneration is to develop agents for osteonecrosis. We aimed to identify the pro-angiogenic and osteogenic efficacy of adipose tissue-derived (AD) pericytes combined with Nel-like protein-1 (NELL-1) to investigate the therapeutic effects on osteonecrosis. Tube formation and cell migration were assessed to determine the pro-angiogenic efficacy. Vessel formation was evaluated in vivo using the chorioallantoic membrane assay. A mouse model with a 2.5 mm necrotic bone fragment in the femoral shaft was used as a substitute for osteonecrosis in humans. Bone formation was assessed radiographically (plain radiographs, three-dimensional images, and quantitative analyses), and histomorphometric analyses were performed. To identify factors related to the effects of NELL-1, analysis using microarrays, qRT-PCR, and Western blotting was performed. The results for pro-angiogenic efficacy evaluation identified synergistic effects of pericytes and NELL-1 on tube formation, cell migration, and vessel formation. For osteogenic efficacy analysis, the mouse model for osteonecrosis was treated in combination with pericytes and NELL-1, and the results showed maximum bone formation using radiographic images and quantitative analyses, compared with other treatment groups and showed robust bone and vessel formation using histomorphometric analysis. We identified an association between FGF2 and the effects of NELL-1 using array-based analysis. Thus, combinatorial therapy using AD pericytes and NELL-1 may have potential as a novel treatment for osteonecrosis.


Assuntos
Tecido Adiposo/citologia , Proteínas de Ligação ao Cálcio/metabolismo , Neovascularização Fisiológica , Osteogênese , Osteonecrose/terapia , Pericitos/citologia , Tecido Adiposo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose , Proteínas de Ligação ao Cálcio/genética , Movimento Celular , Proliferação de Células , Células Cultivadas , Embrião de Mamíferos/irrigação sanguínea , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Osteonecrose/etiologia , Osteonecrose/metabolismo , Osteonecrose/patologia , Pericitos/metabolismo
11.
Int J Mol Sci ; 22(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34576217

RESUMO

Radiation therapy (RT) recruits myeloid cells, leading to an immunosuppressive microenvironment that impedes its efficacy against tumors. Combination of immunotherapy with RT is a potential approach to reversing the immunosuppressive condition and enhancing tumor control after RT. This study aimed to assess the effects of local interleukin-12 (IL-12) therapy on improving the efficacy of RT in a murine prostate cancer model. Combined treatment effectively shrunk the radioresistant tumors by inducing a T helper-1 immune response and influx of CD8+ T cells. It also delayed the radiation-induced vascular damage accompanied by increased α-smooth muscle actin-positive pericyte coverage and blood perfusion. Moreover, RT significantly reduced the IL-12-induced levels of alanine aminotransferase in blood. However, it did not further improve the IL-12-induced anti-tumor effect on distant tumors. Upregulated expression of T-cell exhaustion-associated genes was found in tumors treated with IL-12 only and combined treatment, suggesting that T-cell exhaustion is potentially correlated with tumor relapse in combined treatment. In conclusion, this study illustrated that combination of radiation and local IL-12 therapy enhanced the host immune response and promoted vascular maturation and function. Furthermore, combination treatment was associated with less systemic toxicity than IL-12 alone, providing a potential option for tumor therapy in clinical settings.


Assuntos
Sistema Imunitário/efeitos da radiação , Subunidade p35 da Interleucina-12/metabolismo , Radioterapia/métodos , Actinas/metabolismo , Animais , Linfócitos T CD8-Positivos/metabolismo , Imuno-Histoquímica , Imunossupressores/farmacologia , Imunoterapia , Interferon gama/metabolismo , Fígado/metabolismo , Fígado/patologia , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/metabolismo , Transplante de Neoplasias , Pericitos/metabolismo , Neoplasias da Próstata/metabolismo , Microambiente Tumoral/imunologia
13.
Int J Mol Sci ; 22(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34575914

RESUMO

Recently, the role of kidney pericytes in kidney fibrosis has been investigated. This study aims to evaluate the effect of paricalcitol on hypoxia-induced and TGF-ß1-induced injury in kidney pericytes. The primary cultured pericytes were pretreated with paricalcitol (20 ng/mL) for 90 min before inducing injury, and then they were exposed to TGF-ß1 (5 ng/mL) or hypoxia (1% O2 and 5% CO2). TGF-ß1 increased α-SMA and other fibrosis markers but reduced PDGFRß expression in pericytes, whereas paricalcitol reversed the changes. Paricalcitol inhibited the TGF-ß1-induced cell migration of pericytes. Hypoxia increased TGF-ß1, α-SMA and other fibrosis markers but reduced PDGFRß expression in pericyte, whereas paricalcitol reversed them. Hypoxia activated the HIF-1α and downstream molecules including prolyl hydroxylase 3 and glucose transporter-1, whereas paricalcitol attenuated the activation of the HIF-1α-dependent molecules and TGF-ß1/Smad signaling pathways in hypoxic pericytes. The gene silencing of HIF-1α vanished the hypoxia-induced TGF-ß1, α-SMA upregulation, and PDGFRß downregulation. The effect of paricalcitol on the HIF-1α-dependent changes of fibrosis markers was not significant after the gene silencing of HIF-1α. In addition, hypoxia aggravated the oxidative stress in pericytes, whereas paricalcitol reversed the oxidative stress by increasing the antioxidant enzymes in an HIF-1α-independent manner. In conclusion, paricalcitol improved the phenotype changes of pericyte to myofibroblast in TGF-ß1-stimulated pericytes. In addition, paricalcitol improved the expression of fibrosis markers in hypoxia-exposed pericytes both in an HIF-1α-dependent and independent manner.


Assuntos
Ergocalciferóis/farmacologia , Hipóxia/metabolismo , Pericitos/efeitos dos fármacos , Pericitos/metabolismo , Substâncias Protetoras/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Células Cultivadas , Fibrose , Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Camundongos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Estresse Oxidativo , Pericitos/patologia , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo
14.
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
15.
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
16.
J Gen Virol ; 102(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34424156

RESUMO

Viruses may exploit the cardiovascular system to facilitate transmission or within-host dissemination, and the symptoms of many viral diseases stem at least in part from a loss of vascular integrity. The microvascular architecture is comprised of an endothelial cell barrier ensheathed by perivascular cells (pericytes). Pericytes are antigen-presenting cells (APCs) and play crucial roles in angiogenesis and the maintenance of microvascular integrity through complex reciprocal contact-mediated and paracrine crosstalk with endothelial cells. We here review the emerging ways that viruses interact with pericytes and pay consideration to how these interactions influence microvascular function and viral pathogenesis. Major outcomes of virus-pericyte interactions include vascular leakage or haemorrhage, organ tropism facilitated by barrier disruption, including viral penetration of the blood-brain barrier and placenta, as well as inflammatory, neurological, cognitive and developmental sequelae. The underlying pathogenic mechanisms may include direct infection of pericytes, pericyte modulation by secreted viral gene products and/or the dysregulation of paracrine signalling from or to pericytes. Viruses we cover include the herpesvirus human cytomegalovirus (HCMV, Human betaherpesvirus 5), the retrovirus human immunodeficiency virus (HIV; causative agent of acquired immunodeficiency syndrome, AIDS, and HIV-associated neurocognitive disorder, HAND), the flaviviruses dengue virus (DENV), Japanese encephalitis virus (JEV) and Zika virus (ZIKV), and the coronavirus severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2; causative agent of coronavirus disease 2019, COVID-19). We touch on promising pericyte-focussed therapies for treating the diseases caused by these important human pathogens, many of which are emerging viruses or are causing new or long-standing global pandemics.


Assuntos
Fenômenos Fisiológicos Celulares , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno , Pericitos/virologia , Viroses/metabolismo , Viroses/virologia , Animais , Comunicação Celular , Vírus da Dengue/fisiologia , Gerenciamento Clínico , Células Endoteliais/virologia , Endotélio/metabolismo , Endotélio/virologia , HIV/fisiologia , Humanos , Comunicação Parácrina , SARS-CoV-2/fisiologia , Viroses/diagnóstico , Viroses/terapia , Fenômenos Fisiológicos Virais
17.
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
18.
Cells ; 10(7)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34359953

RESUMO

Many pathological conditions of the brain are associated with structural abnormalities within the neurovascular system and linked to pericyte (PC) loss and/or dysfunction. Since crosstalk between endothelial cells (ECs) and PCs greatly impacts the function of the blood-brain barrier (BBB), effects of PCs on endothelial integrity and function have been investigated extensively. However, the impact of ECs on the function and activity of PCs remains largely unknown. Hence, using co-cultures of human brain vascular PCs with human cerebral microvascular ECs on opposite sides of porous Transwell inserts which facilitates direct EC-PC contact and improves EC barrier function, we analyzed EC-driven transcriptomic changes in PCs using microarrays and changes in cytokines/chemokines using proteome arrays. Gene expression analysis (GEA) in PCs co-cultured with ECs versus PCs cultured alone showed significant upregulation of 1'334 genes and downregulation of 964 genes. GEA in co-cultured PCs revealed increased expression of five prominent PC markers as well as soluble factors, such as transforming growth factor beta, fibroblast growth factor, angiopoietin 1, brain-derived neurotrophic factor, all of which are involved in EC-PC crosstalk and BBB induction. Pathway enrichment analysis of modulated genes showed a strong impact on many inflammatory and extracellular matrix (ECM) pathways including interferon and interleukin signaling, TGF-ß and interleukin-1 regulation of ECM, as well as on the mRNA processing pathway. Interestingly, while co-culture induced the mRNA expression of many chemokines and cytokines, including several CCL- and CXC-motif ligands and interleukins, we observed a decreased expression of the same inflammatory mediators on the protein level. Importantly, in PCs, ECs significantly induced interferon associated proteins (IFIT1, IFI44L, IF127, IFIT3, IFI6, IFI44) with anti-viral actions; downregulated prostaglandin E receptor 2 (prevent COX-2 mediated BBB damage); upregulated fibulin-3 and connective tissue growth factor essential for BBB integrity; and multiple ECMs (collagens and integrins) that inhibit cell migration. Our findings suggest that via direct contact, ECs prime PCs to induce molecules to promote BBB integrity and cell survival during infection and inflammatory insult. Taken together, we provide first evidence that interaction with ECs though porous membranes induces major changes in the transcriptomic and proteomic profile of PCs. ECs influence genes involved in diverse aspects of PC function including PC maturation, cell survival, anti-viral defense, blood flow regulation, immuno-modulation and ECM deposition.


Assuntos
Encéfalo/metabolismo , Movimento Celular/fisiologia , Células Endoteliais/metabolismo , Pericitos/citologia , Transporte Biológico/fisiologia , Endotélio Vascular/metabolismo , Humanos
20.
Elife ; 102021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34280086

RESUMO

Skeletal stem and progenitor cell populations are crucial for bone physiology. Characterization of these cell types remains restricted to heterogenous bulk populations with limited information on whether they are unique or overlap with previously characterized cell types. Here we show, through comprehensive functional and single-cell transcriptomic analyses, that postnatal long bones of mice contain at least two types of bone progenitors with bona fide skeletal stem cell (SSC) characteristics. An early osteochondral SSC (ocSSC) facilitates long bone growth and repair, while a second type, a perivascular SSC (pvSSC), co-emerges with long bone marrow and contributes to shape the hematopoietic stem cell niche and regenerative demand. We establish that pvSSCs, but not ocSSCs, are the origin of bone marrow adipose tissue. Lastly, we also provide insight into residual SSC heterogeneity as well as potential crosstalk between the two spatially distinct cell populations. These findings comprehensively address previously unappreciated shortcomings of SSC research.


Assuntos
Desenvolvimento Ósseo , Osso e Ossos/metabolismo , Células Estromais/metabolismo , Tecido Adiposo , Animais , Medula Óssea , Células da Medula Óssea , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Hematopoéticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pericitos , Nicho de Células-Tronco , Transcriptoma
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