RESUMO
A broad range of brain pathologies critically relies on the vasculature, and cerebrovascular disease is a leading cause of death worldwide. However, the cellular and molecular architecture of the human brain vasculature remains incompletely understood1. Here we performed single-cell RNA sequencing analysis of 606,380 freshly isolated endothelial cells, perivascular cells and other tissue-derived cells from 117 samples, from 68 human fetuses and adult patients to construct a molecular atlas of the developing fetal, adult control and diseased human brain vasculature. We identify extensive molecular heterogeneity of the vasculature of healthy fetal and adult human brains and across five vascular-dependent central nervous system (CNS) pathologies, including brain tumours and brain vascular malformations. We identify alteration of arteriovenous differentiation and reactivated fetal as well as conserved dysregulated genes and pathways in the diseased vasculature. Pathological endothelial cells display a loss of CNS-specific properties and reveal an upregulation of MHC class II molecules, indicating atypical features of CNS endothelial cells. Cell-cell interaction analyses predict substantial endothelial-to-perivascular cell ligand-receptor cross-talk, including immune-related and angiogenic pathways, thereby revealing a central role for the endothelium within brain neurovascular unit signalling networks. Our single-cell brain atlas provides insights into the molecular architecture and heterogeneity of the developing, adult/control and diseased human brain vasculature and serves as a powerful reference for future studies.
Assuntos
Neoplasias Encefálicas , Encéfalo , Malformações Vasculares do Sistema Nervoso Central , Células Endoteliais , Feto , RNA-Seq , Análise da Expressão Gênica de Célula Única , Feminino , Humanos , Masculino , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Encéfalo/embriologia , Encéfalo/metabolismo , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Comunicação Celular , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/citologia , Feto/irrigação sanguínea , Feto/citologia , Feto/embriologia , Malformações Vasculares do Sistema Nervoso Central/patologia , Antígenos HLA-D/metabolismo , Adulto , SaúdeRESUMO
Glioblastomas are among the deadliest human cancers and are highly vascularized. Angiogenesis is dynamic during brain development, almost quiescent in the adult brain but reactivated in vascular-dependent CNS pathologies, including brain tumors. The oncofetal axis describes the reactivation of fetal programs in tumors, but its relevance in endothelial and perivascular cells of the human brain vasculature in glial brain tumors is unexplored. Nucleolin is a regulator of cell proliferation and angiogenesis, but its roles in the brain vasculature remain unknown. Here, we studied the expression of Nucleolin in the neurovascular unit in human fetal brains, adult brains, and human gliomas in vivo as well as its effects on sprouting angiogenesis and endothelial metabolism in vitro. Nucleolin is highly expressed in endothelial and perivascular cells during brain development, downregulated in the adult brain, and upregulated in glioma. Moreover, Nucleolin expression correlated with glioma malignancy in vivo. In culture, siRNA-mediated Nucleolin knockdown reduced human brain endothelial cell (HCMEC) and HUVEC sprouting angiogenesis, proliferation, filopodia extension, and glucose metabolism. Furthermore, inhibition of Nucleolin with the aptamer AS1411 decreased brain endothelial cell proliferation in vitro. Mechanistically, Nucleolin knockdown in HCMECs and HUVECs uncovered regulation of angiogenesis involving VEGFR2 and of endothelial glycolysis. These findings identify Nucleolin as a neurodevelopmental factor reactivated in glioma that promotes sprouting angiogenesis and endothelial metabolism, characterizing Nucleolin as an oncofetal protein. Our findings have potential implications in the therapeutic targeting of glioma.
Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Glioma/metabolismo , Fosfoproteínas/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/patologia , NucleolinaRESUMO
BACKGROUND: In several countries medical prescription of diacetylmorphine is currently being evaluated as a treatment option for heavily dependent narcotic addicts. Because of damaged veins, many patients administer diacetylmorphine intramuscularly or orally. Therefore we characterized the pharmacokinetics of intramuscular and oral diacetylmorphine in the high dose range usually required in narcotic addicts. METHODS: Three intramuscular doses, 3 oral doses, and 1 intravenous dose of diacetylmorphine and oral and intravenous test doses of deuterium-labeled morphine (morphine-N-methyl-d3 [morphine-d3]) were administered to 8 heroin-addicted patients. Arterial plasma concentrations of diacetylmorphine, monoacetylmorphine, morphine, morphine-3-glucuronide, morphine-6-glucuronide, and morphine-d3 were measured by liquid chromatography-mass spectrometry. RESULTS: Intramuscularly administered diacetylmorphine (=200-250 mg) exhibited linear diacetylmorphine, monoacetylmorphine, and morphine kinetics and resulted in sustained diacetylmorphine exposures (bioavailability, 380% +/- 157% [mean +/- SD]) and in lower and delayed peak monoacetylmorphine and morphine concentrations as compared with intravenous administration. Oral diacetylmorphine (=600 mg) yielded negligible systemic diacetylmorphine and monoacetylmorphine exposures but was associated with linear kinetics and high bioavailabilities for morphine (67% +/- 19%), morphine-3-glucuronide (205% +/- 52%), and morphine-6-glucuronide (180% +/- 61%). In addition, oral diacetylmorphine was absorbed more rapidly and to a greater extent than a concomitant test dose of morphine-d3. CONCLUSIONS: On the basis of the linear pharmacokinetics, the high bioavailability of intramuscular diacetylmorphine, and the rapid and extended morphine absorption from oral diacetylmorphine, the intramuscular and oral routes can be recommended as safe and feasible alternatives to the intravenous route for medical prescription of diacetylmorphine.