Fluids and Barriers of the CNS最新文献

{"title":"Single-cell analysis of mesenchymal cells in permeable neural vasculature reveals novel diverse subpopulations of fibroblasts","authors":"William E. Bastedo, R. Wilder Scott, Martin Arostegui, T. Michael Underhill","doi":"10.1186/s12987-024-00535-7","DOIUrl":"https://doi.org/10.1186/s12987-024-00535-7","url":null,"abstract":"In the choroid plexus and pituitary gland, vasculature is known to have a permeable, fenestrated phenotype which allows for the free passage of molecules in contrast to the blood brain barrier observed in the rest of the CNS. The endothelium of these compartments, along with secretory, neural-lineage cells (choroid epithelium and pituitary endocrine cells) have been studied in detail, but less attention has been given to the perivascular mesenchymal cells of these compartments. The Hic1CreERT2 Rosa26LSL−TdTomato mouse model was used in conjunction with a PdgfraH2B−EGFP mouse model to examine mesenchymal cells, which can be subdivided into Pdgfra+ fibroblasts and Pdgfra− pericytes within the choroid plexus (CP) and pituitary gland (PG), by histological, immunofluorescence staining and single-cell RNA-sequencing analyses. We found that both CP and PG possess substantial populations of distinct Hic1+ mesenchymal cells, including an abundance of Pdgfra+ fibroblasts. Within the pituitary, we identified distinct subpopulations of Hic1+ fibroblasts in the glandular anterior pituitary and the neurosecretory posterior pituitary. We also identified multiple distinct markers of CP, PG, and the meningeal mesenchymal compartment, including alkaline phosphatase, indole-n-methyltransferase and CD34. Novel, distinct subpopulations of mesenchymal cells can be found in permeable vascular interfaces, including the CP, PG, and meninges, and make distinct contributions to both organs through the production of structural proteins, enzymes, transporters, and trophic molecules.","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"12 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140573006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[1-11C]-Butanol Positron Emission Tomography reveals an impaired brain to nasal turbinates pathway in aging amyloid positive subjects","authors":"Neel H. Mehta, Xiuyuan Wang, Samantha A. Keil, Ke Xi, Liangdong Zhou, Kevin Lee, Wanbin Tan, Edward Spector, Amirhossein Goldan, James Kelly, Nicolas A. Karakatsanis, P. David Mozley, Sadek Nehmeh, J. Levi Chazen, Simon Morin, John Babich, Jana Ivanidze, Silky Pahlajani, Emily B. Tanzi, Leslie Saint-Louis, Tracy Butler, Kewei Chen, Henry Rusinek, Roxana O. Carare, Yi Li, Gloria C. Chiang, Mony J. de Leon","doi":"10.1186/s12987-024-00530-y","DOIUrl":"https://doi.org/10.1186/s12987-024-00530-y","url":null,"abstract":"Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer’s disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. 24 cognitively normal subjects (≥ 65 years) were dynamically PET imaged for 60 min. using [1-11C]-Butanol. Imaging with either [11C]-PiB or [18F]-FBB identified 8 amyloid PET positive (Aβ+) and 16 Aβ- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the Aβ+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease.","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"35 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140572908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cognitive decline, Aβ pathology, and blood-brain barrier function in aged 5xFAD mice.","authors":"Geetika Nehra, Sasivimon Promsan, Ruedeemars Yubolphan, Wijitra Chumboatong, Pornpun Vivithanaporn, Bryan J Maloney, Anusorn Lungkaphin, Bjoern Bauer, Anika M S Hartz","doi":"10.1186/s12987-024-00531-x","DOIUrl":"10.1186/s12987-024-00531-x","url":null,"abstract":"<p><strong>Background: </strong>Patients with Alzheimer's disease (AD) develop blood-brain barrier dysfunction to varying degrees. How aging impacts Aβ pathology, blood-brain barrier function, and cognitive decline in AD remains largely unknown. In this study, we used 5xFAD mice to investigate changes in Aβ levels, barrier function, and cognitive decline over time.</p><p><strong>Methods: </strong>5xFAD and wild-type (WT) mice were aged between 9.5 and 15.5 months and tested for spatial learning and reference memory with the Morris Water Maze (MWM). After behavior testing, mice were implanted with acute cranial windows and intravenously injected with fluorescent-labeled dextrans to assess their in vivo distribution in the brain by two-photon microscopy. Images were processed and segmented to obtain intravascular intensity, extravascular intensity, and vessel diameters as a measure of barrier integrity. Mice were sacrificed after in vivo imaging to isolate brain and plasma for measuring Aβ levels. The effect of age and genotype were evaluated for each assay using generalized or cumulative-linked logistic mixed-level modeling and model selection by Akaike Information Criterion (AICc). Pairwise comparisons were used to identify outcome differences between the two groups.</p><p><strong>Results: </strong>5xFAD mice displayed spatial memory deficits compared to age-matched WT mice in the MWM assay, which worsened with age. Memory impairment was evident in 5xFAD mice by 2-threefold higher escape latencies, twofold greater cumulative distances until they reach the platform, and twice as frequent use of repetitive search strategies in the pool when compared with age-matched WT mice. Presence of the rd1 allele worsened MWM performance in 5xFAD mice at all ages but did not alter the rate of learning or probe trial outcomes. 9.5-month-old 15.5-month-old 5xFAD mice had twofold higher brain Aβ₄₀ and Aβ₄₂ levels (p < 0.001) and 2.5-fold higher (p = 0.007) plasma Aβ₄₀ levels compared to 9.5-month-old 5xFAD mice. Image analysis showed that vessel diameters and intra- and extravascular dextran intensities were not significantly different in 9.5- and 15.5-month-old 5xFAD mice compared to age-matched WT mice.</p><p><strong>Conclusion: </strong>5xFAD mice continue to develop spatial memory deficits and increased Aβ brain levels while aging. Given in vivo MP imaging limitations, further investigation with smaller molecular weight markers combined with advanced imaging techniques would be needed to reliably assess subtle differences in barrier integrity in aged mice.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"29"},"PeriodicalIF":7.3,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10967049/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140293196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of aquaporin-4 polarization in extracellular solute clearance.","authors":"Laura Bojarskaite, Sahar Nafari, Anne Katrine Ravnanger, Mina Martine Frey, Nadia Skauli, Knut Sindre Åbjørsbråten, Lena Catherine Roth, Mahmood Amiry-Moghaddam, Erlend A Nagelhus, Ole Petter Ottersen, Inger Lise Bogen, Anna E Thoren, Rune Enger","doi":"10.1186/s12987-024-00527-7","DOIUrl":"10.1186/s12987-024-00527-7","url":null,"abstract":"<p><p>Waste from the brain has been shown to be cleared via the perivascular spaces through the so-called glymphatic system. According to this model the cerebrospinal fluid (CSF) enters the brain in perivascular spaces of arteries, crosses the astrocyte endfoot layer, flows through the parenchyma collecting waste that is subsequently drained along veins. Glymphatic clearance is dependent on astrocytic aquaporin-4 (AQP4) water channels that are highly enriched in the endfeet. Even though the polarized expression of AQP4 in endfeet is thought to be of crucial importance for glymphatic CSF influx, its role in extracellular solute clearance has only been evaluated using non-quantitative fluorescence measurements. Here we have quantitatively evaluated clearance of intrastriatally infused small and large radioactively labeled solutes in mice lacking AQP4 (Aqp4^-/-) or lacking the endfoot pool of AQP4 (Snta1^-/-). We confirm that Aqp4^-/- mice show reduced clearance of both small and large extracellular solutes. Moreover, we find that the Snta1^-/- mice have reduced clearance only for the 500 kDa [³H]dextran, but not 0.18 kDa [³H]mannitol suggesting that polarization of AQP4 to the endfeet is primarily important for clearance of large, but not small molecules. Lastly, we observed that clearance of 500 kDa [³H]dextran increased with age in adult mice. Based on our quantitative measurements, we confirm that presence of AQP4 is important for clearance of extracellular solutes, while the perivascular AQP4 localization seems to have a greater impact on clearance of large versus small molecules.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"28"},"PeriodicalIF":7.3,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10964559/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140293197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abcg2a is the functional homolog of human ABCG2 expressed at the zebrafish blood-brain barrier.","authors":"Joanna R Thomas, William J E Frye, Robert W Robey, Andrew C Warner, Donna Butcher, Jennifer L Matta, Tamara C Morgan, Elijah F Edmondson, Paula B Salazar, Suresh V Ambudkar, Michael M Gottesman","doi":"10.1186/s12987-024-00529-5","DOIUrl":"10.1186/s12987-024-00529-5","url":null,"abstract":"<p><strong>Background: </strong>A principal protective component of the mammalian blood-brain barrier (BBB) is the high expression of the multidrug efflux transporters P-glycoprotein (P-gp, encoded by ABCB1) and ABCG2 (encoded by ABCG2) on the lumenal surface of endothelial cells. The zebrafish P-gp homolog Abcb4 is expressed at the BBB and phenocopies human P-gp. Comparatively little is known about the four zebrafish homologs of the human ABCG2 gene: abcg2a, abcg2b, abcg2c, and abcg2d. Here we report the functional characterization and brain tissue distribution of zebrafish ABCG2 homologs.</p><p><strong>Methods: </strong>To determine substrates of the transporters, we stably expressed each in HEK-293 cells and performed cytotoxicity and fluorescent efflux assays with known ABCG2 substrates. To assess the expression of transporter homologs, we used a combination of RNAscope in situ hybridization probes and immunohistochemistry to stain paraffin-embedded sections of adult and larval zebrafish.</p><p><strong>Results: </strong>We found Abcg2a had the greatest substrate overlap with ABCG2, and Abcg2d appeared to be the least functionally similar. We identified abcg2a as the only homolog expressed at the adult and larval zebrafish BBB, based on its localization to claudin-5 positive brain vasculature.</p><p><strong>Conclusions: </strong>These results demonstrate the conserved function of zebrafish Abcg2a and suggest that zebrafish may be an appropriate model organism for studying the role of ABCG2 at the BBB.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"27"},"PeriodicalIF":5.9,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10941402/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140140102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transient but not chronic hyperglycemia accelerates ocular glymphatic transport.","authors":"Christine Delle, Xiaowei Wang, Michael Giannetto, Evan Newbold, Weiguo Peng, Ryszard Stefan Gomolka, Antonio Ladrón-de-Guevara, Neža Cankar, Elise Schiøler Nielsen, Celia Kjaerby, Pia Weikop, Yuki Mori, Maiken Nedergaard","doi":"10.1186/s12987-024-00524-w","DOIUrl":"10.1186/s12987-024-00524-w","url":null,"abstract":"<p><p>Glymphatic transport is vital for the physiological homeostasis of the retina and optic nerve. Pathological alterations of ocular glymphatic fluid transport and enlarged perivascular spaces have been described in glaucomatous mice. It remains to be established how diabetic retinopathy, which impairs vision in about 50% of diabetes patients, impacts ocular glymphatic fluid transport. Here, we examined ocular glymphatic transport in chronic hyperglycemic diabetic mice as well as in healthy mice experiencing a daily transient increase in blood glucose. Mice suffering from severe diabetes for two and four months, induced by streptozotocin, exhibited no alterations in ocular glymphatic fluid transport in the optic nerve compared to age-matched, non-diabetic controls. In contrast, transient increases in blood glucose induced by repeated daily glucose injections in healthy, awake, non-diabetic mice accelerated antero- and retrograde ocular glymphatic transport. Structural analysis showed enlarged perivascular spaces in the optic nerves of glucose-treated mice, which were absent in diabetic mice. Thus, transient repeated hyperglycemic events, but not constant hyperglycemia, ultimately enlarge perivascular spaces in the murine optic nerve. These findings indicate that fluid transport in the mouse eye is vulnerable to fluctuating glycemic levels rather than constant hyperglycemia, suggesting that poor glycemic control drives glymphatic malfunction and perivascular enlargement in the optic nerve.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"26"},"PeriodicalIF":7.3,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10935920/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140109793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Freezing of gait in idiopathic normal pressure hydrocephalus.","authors":"Carl-Johan Kihlstedt, Jan Malm, Alfonso Fasano, David Bäckström","doi":"10.1186/s12987-024-00522-y","DOIUrl":"10.1186/s12987-024-00522-y","url":null,"abstract":"<p><strong>Background: </strong>Reports of freezing of gait (FoG) in idiopathic normal pressure hydrocephalus (iNPH) are few and results are variable. This study's objective was to evaluate the frequency of FoG in a large cohort of iNPH patients, identify FoG-associated factors, and assess FoG's responsiveness to shunt surgery.</p><p><strong>Methods: </strong>Videotaped standardized gait protocols with iNPH patients pre- and post-shunt surgery (n = 139; median age 75 (71-79) years; 48 women) were evaluated for FoG episodes by two observers (Cohens kappa = 0.9, p < 0.001). FoG episodes were categorized. Mini-mental state examination (MMSE) and MRI white matter hyperintensities (WMH) assessment using the Fazekas scale were performed. CSF was analyzed for Beta-amyloid, Tau, and Phospho-tau. Patients with and without FoG were compared.</p><p><strong>Results: </strong>Twenty-two patients (16%) displayed FoG at baseline, decreasing to seven (8%) after CSF shunt surgery (p = 0.039). The symptom was most frequently exhibited during turning (n = 16, 73%). Patients displaying FoG were older (77.5 vs. 74.6 years; p = 0.029), had a slower walking speed (0.59 vs. 0.89 m/s; p < 0.001), a lower Tinetti POMA score (6.8 vs. 10.8; p < 0.001), lower MMSE score (21.3 vs. 24.0; p = 0.031), and longer disease duration (4.2 vs. 2.3 years; p < 0.001) compared to patients not displaying FoG. WMH or CSF biomarkers did not differ between the groups.</p><p><strong>Conclusions: </strong>FoG is occurring frequently in iNPH patients and may be considered a typical feature of iNPH. FoG in iNPH was associated with higher age, longer disease duration, worse cognitive function, and a more unstable gait. Shunt surgery seems to improve the symptom.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"22"},"PeriodicalIF":7.3,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10921745/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140059005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validating the accuracy of real-time phase-contrast MRI and quantifying the effects of free breathing on cerebrospinal fluid dynamics","authors":"Pan Liu, Kimi Owashi, Heimiri Monnier, Serge Metanbou, Cyrille Capel, Olivier Balédent","doi":"10.1186/s12987-024-00520-0","DOIUrl":"https://doi.org/10.1186/s12987-024-00520-0","url":null,"abstract":"Understanding of the cerebrospinal fluid (CSF) circulation is essential for physiological studies and clinical diagnosis. Real-time phase contrast sequences (RT-PC) can quantify beat-to-beat CSF flow signals. However, the detailed effects of free-breathing on CSF parameters are not fully understood. This study aims to validate RT-PC’s accuracy by comparing it with the conventional phase-contrast sequence (CINE-PC) and quantify the effect of free-breathing on CSF parameters at the intracranial and extracranial levels using a time-domain multiparametric analysis method. Thirty-six healthy participants underwent MRI in a 3T scanner for CSF oscillations quantification at the cervical spine (C2-C3) and Sylvian aqueduct, using CINE-PC and RT-PC. CINE-PC uses 32 velocity maps to represent dynamic CSF flow over an average cardiac cycle, while RT-PC continuously quantifies CSF flow over 45-seconds. Free-breathing signals were recorded from 25 participants. RT-PC signal was segmented into independent cardiac cycle flow curves (Qt) and reconstructed into an averaged Qt. To assess RT-PC’s accuracy, parameters such as segmented area, flow amplitude, and stroke volume (SV) of the reconstructed Qt from RT-PC were compared with those derived from the averaged Qt generated by CINE-PC. The breathing signal was used to categorize the Qt into expiratory or inspiratory phases, enabling the reconstruction of two Qt for inspiration and expiration. The breathing effects on various CSF parameters can be quantified by comparing these two reconstructed Qt. RT-PC overestimated CSF area (82.7% at aqueduct, 11.5% at C2-C3) compared to CINE-PC. Stroke volumes for CINE-PC were 615 mm³ (aqueduct) and 43 mm³ (spinal), and 581 mm³ (aqueduct) and 46 mm³ (spinal) for RT-PC. During thoracic pressure increase, spinal CSF net flow, flow amplitude, SV, and cardiac period increased by 6.3%, 6.8%, 14%, and 6%, respectively. Breathing effects on net flow showed a significant phase difference compared to the other parameters. Aqueduct-CSF flows were more affected by breathing than spinal-CSF. RT-PC accurately quantifies CSF oscillations in real-time and eliminates the need for cardiac synchronization, enabling the quantification of the cardiac and breathing components of CSF flow. This study quantifies the impact of free-breathing on CSF parameters, offering valuable physiological references for understanding the effects of breathing on CSF dynamics.","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"47 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The proteome of the blood-brain barrier in rat and mouse: highly specific identification of proteins on the luminal surface of brain microvessels by in vivo glycocapture.","authors":"Tammy-Lynn Tremblay, Wael Alata, Jacqueline Slinn, Ewa Baumann, Christie E Delaney, Maria Moreno, Arsalan S Haqqani, Danica B Stanimirovic, Jennifer J Hill","doi":"10.1186/s12987-024-00523-x","DOIUrl":"10.1186/s12987-024-00523-x","url":null,"abstract":"<p><strong>Background: </strong>The active transport of molecules into the brain from blood is regulated by receptors, transporters, and other cell surface proteins that are present on the luminal surface of endothelial cells at the blood-brain barrier (BBB). However, proteomic profiling of proteins present on the luminal endothelial cell surface of the BBB has proven challenging due to difficulty in labelling these proteins in a way that allows efficient purification of these relatively low abundance cell surface proteins.</p><p><strong>Methods: </strong>Here we describe a novel perfusion-based labelling workflow: in vivo glycocapture. This workflow relies on the oxidation of glycans present on the luminal vessel surface via perfusion of a mild oxidizing agent, followed by subsequent isolation of glycoproteins by covalent linkage of their oxidized glycans to hydrazide beads. Mass spectrometry-based identification of the isolated proteins enables high-confidence identification of endothelial cell surface proteins in rats and mice.</p><p><strong>Results: </strong>Using the developed workflow, 347 proteins were identified from the BBB in rat and 224 proteins in mouse, for a total of 395 proteins in both species combined. These proteins included many proteins with transporter activity (73 proteins), cell adhesion proteins (47 proteins), and transmembrane signal receptors (31 proteins). To identify proteins that are enriched in vessels relative to the entire brain, we established a vessel-enrichment score and showed that proteins with a high vessel-enrichment score are involved in vascular development functions, binding to integrins, and cell adhesion. Using publicly-available single-cell RNAseq data, we show that the proteins identified by in vivo glycocapture were more likely to be detected by scRNAseq in endothelial cells than in any other cell type. Furthermore, nearly 50% of the genes encoding cell-surface proteins that were detected by scRNAseq in endothelial cells were also identified by in vivo glycocapture.</p><p><strong>Conclusions: </strong>The proteins identified by in vivo glycocapture in this work represent the most complete and specific profiling of proteins on the luminal BBB surface to date. The identified proteins reflect possible targets for the development of antibodies to improve the crossing of therapeutic proteins into the brain and will contribute to our further understanding of BBB transport mechanisms.</p>","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"21 1","pages":"23"},"PeriodicalIF":7.3,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10910681/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140021306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The genetic basis of hydrocephalus: genes, pathways, mechanisms, and global impact","authors":"Andrew T. Hale, Hunter Boudreau, Rishi Devulapalli, Phan Q. Duy, Travis J. Atchley, Michael C. Dewan, Mubeen Goolam, Graham Fieggen, Heather L. Spader, Anastasia A. Smith, Jeffrey P. Blount, James M. Johnston, Brandon G. Rocque, Curtis J. Rozzelle, Zechen Chong, Jennifer M. Strahle, Steven J. Schiff, Kristopher T. Kahle","doi":"10.1186/s12987-024-00513-z","DOIUrl":"https://doi.org/10.1186/s12987-024-00513-z","url":null,"abstract":"Hydrocephalus (HC) is a heterogenous disease characterized by alterations in cerebrospinal fluid (CSF) dynamics that may cause increased intracranial pressure. HC is a component of a wide array of genetic syndromes as well as a secondary consequence of brain injury (intraventricular hemorrhage (IVH), infection, etc.) that can present across the age spectrum, highlighting the phenotypic heterogeneity of the disease. Surgical treatments include ventricular shunting and endoscopic third ventriculostomy with or without choroid plexus cauterization, both of which are prone to failure, and no effective pharmacologic treatments for HC have been developed. Thus, there is an urgent need to understand the genetic architecture and molecular pathogenesis of HC. Without this knowledge, the development of preventive, diagnostic, and therapeutic measures is impeded. However, the genetics of HC is extraordinarily complex, based on studies of varying size, scope, and rigor. This review serves to provide a comprehensive overview of genes, pathways, mechanisms, and global impact of genetics contributing to all etiologies of HC in humans.","PeriodicalId":12321,"journal":{"name":"Fluids and Barriers of the CNS","volume":"42 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140025848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}