Discovery of meningeal lymphatic vessels (LVs) in the dura mater, also known as dural LVs (dLVs) that depend on vascular endothelial growth factor C expression, has raised interest in their possible involvement in Alzheimer's disease (AD). Here we find that in the APdE9 and 5xFAD mouse models of AD, dural amyloid-β (Aβ) is confined to blood vessels and dLV morphology or function is not altered. The induction of sustained dLV atrophy or hyperplasia in the AD mice by blocking or overexpressing vascular endothelial growth factor C, impaired or improved, respectively, macromolecular cerebrospinal fluid (CSF) drainage to cervical lymph nodes.
View Article and Find Full Text PDFTimely relief of edema and clearance of waste products, as well as promotion of anti-inflammatory immune responses, reduce ischemic stroke pathology, and attenuate harmful long-term effects post-stroke. The discovery of an extensive and functional lymphatic vessel system in the outermost meningeal layer, dura mater, has opened up new possibilities to facilitate post-stroke recovery by inducing dural lymphatic vessel (dLV) growth via a single injection of a vector encoding vascular endothelial growth factor C (VEGF-C). In the present study, we aimed to improve post-stroke outcomes by inducing dLV growth in mice.
View Article and Find Full Text PDFBackground: Preclinical studies have shown the therapeutic potential of VEGF-B (vascular endothelial growth factor B) in revascularization of the ischemic myocardium, but the associated cardiac hypertrophy and adverse side effects remain a concern. To understand the importance of endothelial proliferation and migration for the beneficial versus adverse effects of VEGF-B in the heart, we explored the cardiac effects of autocrine versus paracrine VEGF-B expression in transgenic and gene-transduced mice.
Methods: We used single-cell RNA sequencing to compare cardiac endothelial gene expression in VEGF-B transgenic mouse models.
Background: Recent decades have seen changes in the urological treatment of myelomeningocele (MMC). We aimed to evaluate the urological outcomes in post-pubertal patients and to clarify associations with walking status, hydrocephalus, and sex.
Methods: A retrospective study of 103 MMC patients at their final pediatric urological control.
Leptomeninges, consisting of the pia mater and arachnoid, form a connective tissue investment and barrier enclosure of the brain. The exact nature of leptomeningeal cells has long been debated. In this study, we identify five molecularly distinct fibroblast-like transcriptomes in cerebral leptomeninges; link them to anatomically distinct cell types of the pia, inner arachnoid, outer arachnoid barrier, and dural border layer; and contrast them to a sixth fibroblast-like transcriptome present in the choroid plexus and median eminence.
View Article and Find Full Text PDFThe recent discovery of lymphatic vessels (LVs) in the dura mater, the outermost layer of meninges around the central nervous system (CNS), has opened a possibility for the development of alternative therapeutics for CNS disorders. The vascular endothelial growth factor C (VEGF-C)/VEGF receptor 3 (VEGFR3) signaling pathway is essential for the development and maintenance of dural LVs. However, its significance in mediating dural lymphatic function in CNS autoimmunity is unclear.
View Article and Find Full Text PDFUnderstanding the pathological mechanisms unfolding after chronic traumatic brain injury (TBI) could reveal new therapeutic entry points. During the post-TBI sequel, the involvement of cerebrospinal fluid drainage through the meningeal lymphatic vessels was proposed. Here, we used K14-VEGFR3-Ig transgenic mice to analyze whether a developmental dysfunction of meningeal lymphatic vessels modifies post-TBI pathology.
View Article and Find Full Text PDFRationale: The recently discovered meningeal lymphatic vessels (mLVs) have been proposed to be the missing link between the immune and the central nervous system. The role of mLVs in modulating the neuro-immune response following a traumatic brain injury (TBI), however, has not been analyzed. Parenchymal T lymphocyte infiltration has been previously reported as part of secondary events after TBI, suggestive of an adaptive neuro-immune response.
View Article and Find Full Text PDFAngiopoietin-2 (Ang2), a ligand of the endothelial Tie2 tyrosine kinase, is involved in vascular inflammation and leakage in critically ill patients. However, the role of Ang2 in demyelinating central nervous system (CNS) autoimmune diseases is unknown. Here, we report that Ang2 is critically involved in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), a rodent model of multiple sclerosis.
View Article and Find Full Text PDFImmune surveillance against pathogens and tumours in the central nervous system is thought to be limited owing to the lack of lymphatic drainage. However, the characterization of the meningeal lymphatic network has shed light on previously unappreciated ways that an immune response can be elicited to antigens that are expressed in the brain. Despite progress in our understanding of the development and structure of the meningeal lymphatic system, the contribution of this network in evoking a protective antigen-specific immune response in the brain remains unclear.
View Article and Find Full Text PDFCranial lymphatic vessels (LVs) are involved in the transport of fluids, macromolecules and central nervous system (CNS) immune responses. Little information about spinal LVs is available, because these delicate structures are embedded within vertebral tissues and difficult to visualize using traditional histology. Here we show an extended vertebral column LV network using three-dimensional imaging of decalcified iDISCO-clarified spine segments.
View Article and Find Full Text PDFThe lymphatic vessels can be selectively stimulated to grow in adult mice, rats and pigs by application of viral vectors expressing the lymphangiogenic factors VEGF-C or VEGF-D. Vice versa, lymphangiogenesis in various pathological settings can be inhibited by the blocking of the VEGF-C/VEGFR3 interaction using a ligand-binding soluble form of VEGFR3. Furthermore, the recently discovered plasticity of meningeal and lacteal lymphatic vessels provides novel opportunities for their manipulation in disease.
View Article and Find Full Text PDFThe recent discovery of meningeal lymphatic vessels (LVs) has raised interest in their possible involvement in neuropathological processes, yet little is known about their development or maintenance. We show here that meningeal LVs develop postnatally, appearing first around the foramina in the basal parts of the skull and spinal canal, sprouting along the blood vessels and cranial and spinal nerves to various parts of the meninges surrounding the central nervous system (CNS). VEGF-C, expressed mainly in vascular smooth muscle cells, and VEGFR3 in lymphatic endothelial cells were essential for their development, whereas VEGF-D deletion had no effect.
View Article and Find Full Text PDFRecent discoveries of the glymphatic system and of meningeal lymphatic vessels have generated a lot of excitement, along with some degree of skepticism. Here, we summarize the state of the field and point out the gaps of knowledge that should be filled through further research. We discuss the glymphatic system as a system that allows CNS perfusion by the cerebrospinal fluid (CSF) and interstitial fluid (ISF).
View Article and Find Full Text PDFThe central nervous system (CNS) is considered an organ devoid of lymphatic vasculature. Yet, part of the cerebrospinal fluid (CSF) drains into the cervical lymph nodes (LNs). The mechanism of CSF entry into the LNs has been unclear.
View Article and Find Full Text PDFIn glaucoma, aqueous outflow into the Schlemm's canal (SC) is obstructed. Despite striking structural and functional similarities with the lymphatic vascular system, it is unknown whether the SC is a blood or lymphatic vessel. Here, we demonstrated the expression of lymphatic endothelial cell markers by the SC in murine and zebrafish models as well as in human eye tissue.
View Article and Find Full Text PDFLevosimendan has been developed for the treatment of decompensated heart failure and is used intravenously when patients with heart failure require immediate initiation of drug therapy. It increases cardiac contractility and induces vasodilatation. The pharmacokinetics of levosimendan are linear at the therapeutic dose range of 0.
View Article and Find Full Text PDFObjective: The purpose of this study was to investigate the pharmacokinetics of levosimendan and to determine the primary pharmacokinetic parameters of the pharmacologically active metabolite OR-1896 in rapid and slow acetylators.
Methods: Levosimendan was administered as a constant rate (0.1 microg/(kg min)) i.
The objective of this study was to explore the pharmacodynamics and pharmacokinetics of oral levosimendan in patients with severe congestive heart failure. This was a randomized, parallel-group, double-blind, placebo-controlled trial. Oral levosimendan 2 to 8 mg daily or placebo was administered to 25 patients with New York Heart Association class III-IV congestive heart failure for 4 weeks.
View Article and Find Full Text PDFPediatr Crit Care Med
September 2004
Objective: The objective of the study was to evaluate the pharmacokinetics, hemodynamic effects, and safety of levosimendan in children with congenital heart disease.
Design: Open, one group, single-dose study.
Setting: Cardiac catheter laboratory in a pediatric cardiology department of a university hospital.
Cardiovasc Drugs Ther
September 2004
Objective: The aim was to study the pharmacodynamic interactions and safety of the co-administration of the calcium sensitizer levosimendan and the calcium antagonist felodipine in patients with coronary heart disease (CHD) and with normal ejection fraction (EF).
Methods: The study was a randomized, double blind, placebo-controlled, crossover study in 24 male patients with Canadian Cardiovascular Society (CCS) class II CHD, consisting of four treatment periods, each period lasting for 7-10 days. In the first period the patients received either oral levosimendan (LS) (0.
Aims: To measure physicians' use of the alcometer (breath analysis test) and their documentation of alcohol-related findings among their patients.
Methods: Over one weekend, during which 100 adults attended the emergency clinic of a university hospital, data were collected on patients' alcohol consumption, physicians' use of an alcometer and alcohol-related documentation. Heavy drinkers were defined by the patient's response to a written questionnaire: Five-Shot total score >or=3 points, and/or >or=7 drinks per one occasion.
Aims: The purpose of the study was to characterize the pharmacokinetics of levosimendan and its metabolites OR-1855 and OR-1896 in patients with congestive heart failure.
Methods: Levosimendan was administered as a continuous intravenous infusion for 7 days. Twelve subjects received the drug at an infusion rate of 0.
Positive inotropic drugs have various mechanisms of action. Long-term use of cyclic adenosine monophosphate (cAMP)-dependent drugs has adverse effects on the prognosis of heart failure patients, whereas digoxin has neutral effect on mortality. There are, however, little data on the effects of intravenous inotropic drugs on the outcome of patients.
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