Pub Date : 2024-09-17DOI: 10.1177/0271678x241283226
Julia HI Wiersinga, Frank J Wolters, Mike JL Peters, Hanneke FM Rhodius-Meester, Marijke C Trappenburg, Majon Muller
Orthostatic hypotension(OH) is highly prevalent in ageing populations and may contribute to cognitive decline through cerebral small vessel disease(CSVD). Research on the association between OH and CSVD is fragmented and inconsistent. We systematically reviewed the literature for studies assessing the association between OH and CSVD, published until December 1st 2023 in MEDLINE, PubMed or Web of Science. We included studies with populations aged ≥60, that assessed OH in relation to CSVD including white matter hyperintensities(WMH), lacunes and cerebral microbleeds. Modified JBI checklist was used to assess risk of bias. A narrative synthesis of the results was presented. Of 3180 identified studies, eighteen were included. Fifteen studies reported on WMH, four on lacunes, seven on microbleeds. Six of fifteen studies on WMH found that OH was related to an increased burden of WMH, neither longitudinal studies found associations with WMH progression. Findings were inconsistent across studies concerning lacunes and microbleeds. Across outcomes, adequate adjustment for systolic blood pressure tended to coincide with smaller effect estimates. Current evidence on the OH-CSVD association originates mostly from cross-sectional studies, providing inconsistent and inconclusive results. Longitudinal studies using standardized and fine-grained assessment of OH and CSVD and adequate adjustment for supine blood pressure are warranted.
{"title":"Orthostatic hypotension and cerebral small vessel disease: A systematic review","authors":"Julia HI Wiersinga, Frank J Wolters, Mike JL Peters, Hanneke FM Rhodius-Meester, Marijke C Trappenburg, Majon Muller","doi":"10.1177/0271678x241283226","DOIUrl":"https://doi.org/10.1177/0271678x241283226","url":null,"abstract":"Orthostatic hypotension(OH) is highly prevalent in ageing populations and may contribute to cognitive decline through cerebral small vessel disease(CSVD). Research on the association between OH and CSVD is fragmented and inconsistent. We systematically reviewed the literature for studies assessing the association between OH and CSVD, published until December 1st 2023 in MEDLINE, PubMed or Web of Science. We included studies with populations aged ≥60, that assessed OH in relation to CSVD including white matter hyperintensities(WMH), lacunes and cerebral microbleeds. Modified JBI checklist was used to assess risk of bias. A narrative synthesis of the results was presented. Of 3180 identified studies, eighteen were included. Fifteen studies reported on WMH, four on lacunes, seven on microbleeds. Six of fifteen studies on WMH found that OH was related to an increased burden of WMH, neither longitudinal studies found associations with WMH progression. Findings were inconsistent across studies concerning lacunes and microbleeds. Across outcomes, adequate adjustment for systolic blood pressure tended to coincide with smaller effect estimates. Current evidence on the OH-CSVD association originates mostly from cross-sectional studies, providing inconsistent and inconclusive results. Longitudinal studies using standardized and fine-grained assessment of OH and CSVD and adequate adjustment for supine blood pressure are warranted.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-10DOI: 10.1177/0271678x241281137
Caroline Robert, Lieng-Hsi Ling, Eugene SJ Tan, Narayanaswamy Venketasubramanian, Shir Lynn Lim, Lingli Gong, Josephine Lunaria Berboso, Arthur Mark Richards, Christopher Chen, Saima Hilal
We examined the relative associations of aortic and carotid artery stiffness with cerebrovascular disease (CeVD), cognition, and dementia subtypes in a memory clinic cohort of 272 participants (mean age = 75.4, SD = 6.8). We hypothesized that carotid artery stiffness would have greater effects on outcomes, given its proximate relationship to the brain. Aortic and carotid artery stiffness were assessed with applanation tonometry and carotid ultrasonography, respectively. CeVD markers included white matter hyperintensities (WMH), lacunes, cerebral microbleeds, cortical infarcts, and intracranial stenosis. Cognition was assessed by the Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and a neuropsychological battery. Multivariable linear regression was conducted to determine associations of arterial stiffness with WMH and cognition, while logistic regression analysed associations with CeVD markers and dementia subtypes. Carotid artery stiffness z-score was associated with WMH, cortical infarcts, vascular cognitive impairment, and MMSE, independent of age, sex, education, vascular risk factors, and aortic stiffness z-score. Although aortic stiffness z-score was independently associated with cortical infarcts, this became non-significant after further adjusting for carotid artery stiffness z-score. We found that carotid artery stiffness had greater effects on CeVD, cognitive function and impairment in memory clinic patients compared to aortic stiffness.
{"title":"The relative associations of aortic and carotid artery stiffness with CeVD and cognition","authors":"Caroline Robert, Lieng-Hsi Ling, Eugene SJ Tan, Narayanaswamy Venketasubramanian, Shir Lynn Lim, Lingli Gong, Josephine Lunaria Berboso, Arthur Mark Richards, Christopher Chen, Saima Hilal","doi":"10.1177/0271678x241281137","DOIUrl":"https://doi.org/10.1177/0271678x241281137","url":null,"abstract":"We examined the relative associations of aortic and carotid artery stiffness with cerebrovascular disease (CeVD), cognition, and dementia subtypes in a memory clinic cohort of 272 participants (mean age = 75.4, SD = 6.8). We hypothesized that carotid artery stiffness would have greater effects on outcomes, given its proximate relationship to the brain. Aortic and carotid artery stiffness were assessed with applanation tonometry and carotid ultrasonography, respectively. CeVD markers included white matter hyperintensities (WMH), lacunes, cerebral microbleeds, cortical infarcts, and intracranial stenosis. Cognition was assessed by the Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and a neuropsychological battery. Multivariable linear regression was conducted to determine associations of arterial stiffness with WMH and cognition, while logistic regression analysed associations with CeVD markers and dementia subtypes. Carotid artery stiffness z-score was associated with WMH, cortical infarcts, vascular cognitive impairment, and MMSE, independent of age, sex, education, vascular risk factors, and aortic stiffness z-score. Although aortic stiffness z-score was independently associated with cortical infarcts, this became non-significant after further adjusting for carotid artery stiffness z-score. We found that carotid artery stiffness had greater effects on CeVD, cognitive function and impairment in memory clinic patients compared to aortic stiffness.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-10DOI: 10.1177/0271678x241270283
Wesley T Richerson, Megan Aumann, Alexander K Song, Jarrod J Eisma, Samantha Davis, Lauren Milner, Maria Garza, L Taylor Davis, Dann Martin, Lori C Jordan, Manus J Donahue
Sickle cell disease (SCD) is the most common genetic blood disorder, characterized by red cell hemolysis, anemia, and corresponding increased compensatory cerebral blood flow (CBF). SCD patients are at high risk for cerebral infarcts and CBF quantification is likely critical to assess infarct risk. Infarcts primarily localize to white matter (WM), yet arterial spin labeling (ASL) MRI, the most common non-invasive CBF approach, has poor WM CBF sensitivity owing to low WM CBF and long WM bolus arrival time (BAT). We hypothesize that anemia, and associated cerebral hyperemia, in SCD leads to improved WM detection with ASL. We performed 3-Tesla multi-delay pulsed ASL in SCD (n = 35; age = 30.5 ± 8.3 years) and control (n = 15; age = 28.7 ± 4.5 years) participants and applied t-tests at each inversion time within different flow territories, and determined which regions were significantly above noise floor (criteria: one-sided p < 0.05). Total WM CBF-weighted signal was primarily detectable outside of borderzone regions in SCD (CBF = 17.7 [range = 12.9–25.0] mL/100 g/min), but was largely unphysiological in control (CBF = 8.1 [range = 7.6–9.9)] mL/100 g/min) participants. WM BAT was reduced in SCD versus control participants (ΔBAT = 37 [range = 46–70] ms) and BAT directly correlated with hematocrit (Spearman’s-ρ = 0.62; p < 0.001). Findings support the feasibility of WM CBF quantification using ASL in SCD participants for appropriately parameterized protocols.
{"title":"Detectability of white matter cerebral blood flow using arterial spin labeling MRI in patients with sickle cell disease: Relevance of flow territory, bolus arrival time, and hematocrit","authors":"Wesley T Richerson, Megan Aumann, Alexander K Song, Jarrod J Eisma, Samantha Davis, Lauren Milner, Maria Garza, L Taylor Davis, Dann Martin, Lori C Jordan, Manus J Donahue","doi":"10.1177/0271678x241270283","DOIUrl":"https://doi.org/10.1177/0271678x241270283","url":null,"abstract":"Sickle cell disease (SCD) is the most common genetic blood disorder, characterized by red cell hemolysis, anemia, and corresponding increased compensatory cerebral blood flow (CBF). SCD patients are at high risk for cerebral infarcts and CBF quantification is likely critical to assess infarct risk. Infarcts primarily localize to white matter (WM), yet arterial spin labeling (ASL) MRI, the most common non-invasive CBF approach, has poor WM CBF sensitivity owing to low WM CBF and long WM bolus arrival time (BAT). We hypothesize that anemia, and associated cerebral hyperemia, in SCD leads to improved WM detection with ASL. We performed 3-Tesla multi-delay pulsed ASL in SCD (n = 35; age = 30.5 ± 8.3 years) and control (n = 15; age = 28.7 ± 4.5 years) participants and applied t-tests at each inversion time within different flow territories, and determined which regions were significantly above noise floor (criteria: one-sided p < 0.05). Total WM CBF-weighted signal was primarily detectable outside of borderzone regions in SCD (CBF = 17.7 [range = 12.9–25.0] mL/100 g/min), but was largely unphysiological in control (CBF = 8.1 [range = 7.6–9.9)] mL/100 g/min) participants. WM BAT was reduced in SCD versus control participants (ΔBAT = 37 [range = 46–70] ms) and BAT directly correlated with hematocrit (Spearman’s-ρ = 0.62; p < 0.001). Findings support the feasibility of WM CBF quantification using ASL in SCD participants for appropriately parameterized protocols.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-10DOI: 10.1177/0271678x241280775
Gary P Morris, Catherine G Foster, Brad A Sutherland, Søren Grubb
The close spatial relationship between microglia and cerebral blood vessels implicates microglia in vascular development, homeostasis and disease. In this study we used the publicly available Cortical MM^3 electron microscopy dataset to systematically investigate microglial interactions with the vasculature. Our analysis revealed that approximately 20% of microglia formed direct contacts with blood vessels through gaps between adjacent astrocyte endfeet. We termed these contact points “plugs”. Plug-forming microglia exhibited closer proximity to blood vessels than non-plug forming microglia and formed multiple plugs, predominantly near the soma, ranging in surface area from ∼0.01 μm2 to ∼15 μm2. Plugs were enriched at the venule end of the vascular tree and displayed a preference for contacting endothelial cells over pericytes at a ratio of 3:1. In summary, we provide novel insights into the ultrastructural relationship between microglia and the vasculature, laying a foundation for understanding how these contacts contribute to the functional cross-talk between microglia and cells of the vasculature in health and disease.
{"title":"Microglia contact cerebral vasculature through gaps between astrocyte endfeet","authors":"Gary P Morris, Catherine G Foster, Brad A Sutherland, Søren Grubb","doi":"10.1177/0271678x241280775","DOIUrl":"https://doi.org/10.1177/0271678x241280775","url":null,"abstract":"The close spatial relationship between microglia and cerebral blood vessels implicates microglia in vascular development, homeostasis and disease. In this study we used the publicly available Cortical MM^3 electron microscopy dataset to systematically investigate microglial interactions with the vasculature. Our analysis revealed that approximately 20% of microglia formed direct contacts with blood vessels through gaps between adjacent astrocyte endfeet. We termed these contact points “plugs”. Plug-forming microglia exhibited closer proximity to blood vessels than non-plug forming microglia and formed multiple plugs, predominantly near the soma, ranging in surface area from ∼0.01 μm<jats:sup>2</jats:sup> to ∼15 μm<jats:sup>2</jats:sup>. Plugs were enriched at the venule end of the vascular tree and displayed a preference for contacting endothelial cells over pericytes at a ratio of 3:1. In summary, we provide novel insights into the ultrastructural relationship between microglia and the vasculature, laying a foundation for understanding how these contacts contribute to the functional cross-talk between microglia and cells of the vasculature in health and disease.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-15DOI: 10.1177/0271678x241254718
Matej Skrobot, Rafael De Sa, Josefine Walter, Arend Vogt, Raik Paulat, Janet Lips, Larissa Mosch, Susanne Mueller, Sina Dominiak, Robert Sachdev, Philipp Boehm-Sturm, Ulrich Dirnagl, Matthias Endres, Christoph Harms, Nikolaus Wenger
Accurate assessment of post-stroke deficits is crucial in translational research. Recent advances in machine learning offer precise quantification of rodent motor behavior post-stroke, yet detecting lesion-specific upper extremity deficits remains unclear. Employing proximal middle cerebral artery occlusion (MCAO) and cortical photothrombosis (PT) in mice, we assessed post-stroke impairments via the Staircase test. Lesion locations were identified using 7 T-MRI. Machine learning was applied to reconstruct forepaw kinematic trajectories and feature analysis was achieved with MouseReach, a new data-processing toolbox. Lesion reconstructions pinpointed ischemic centers in the striatum (MCAO) and sensorimotor cortex (PT). Pellet retrieval alterations were observed, but were unrelated to overall stroke volume. Instead, forepaw slips and relative reaching success correlated with increasing cortical lesion size in both models. Striatal lesion size after MCAO was associated with prolonged reach durations that occurred with delayed symptom onset. Further analysis on the impact of selective serotonin reuptake inhibitors in the PT model revealed no clear treatment effects but replicated strong effect sizes of slips for post-stroke deficit detection. In summary, refined movement analysis unveiled specific deficits in two widely-used mouse stroke models, emphasizing the value of deep behavioral profiling in preclinical stroke research to enhance model validity for clinical translation.
{"title":"Refined movement analysis in the Staircase test reveals differential motor deficits in mouse models of stroke","authors":"Matej Skrobot, Rafael De Sa, Josefine Walter, Arend Vogt, Raik Paulat, Janet Lips, Larissa Mosch, Susanne Mueller, Sina Dominiak, Robert Sachdev, Philipp Boehm-Sturm, Ulrich Dirnagl, Matthias Endres, Christoph Harms, Nikolaus Wenger","doi":"10.1177/0271678x241254718","DOIUrl":"https://doi.org/10.1177/0271678x241254718","url":null,"abstract":"Accurate assessment of post-stroke deficits is crucial in translational research. Recent advances in machine learning offer precise quantification of rodent motor behavior post-stroke, yet detecting lesion-specific upper extremity deficits remains unclear. Employing proximal middle cerebral artery occlusion (MCAO) and cortical photothrombosis (PT) in mice, we assessed post-stroke impairments via the Staircase test. Lesion locations were identified using 7 T-MRI. Machine learning was applied to reconstruct forepaw kinematic trajectories and feature analysis was achieved with MouseReach, a new data-processing toolbox. Lesion reconstructions pinpointed ischemic centers in the striatum (MCAO) and sensorimotor cortex (PT). Pellet retrieval alterations were observed, but were unrelated to overall stroke volume. Instead, forepaw slips and relative reaching success correlated with increasing cortical lesion size in both models. Striatal lesion size after MCAO was associated with prolonged reach durations that occurred with delayed symptom onset. Further analysis on the impact of selective serotonin reuptake inhibitors in the PT model revealed no clear treatment effects but replicated strong effect sizes of slips for post-stroke deficit detection. In summary, refined movement analysis unveiled specific deficits in two widely-used mouse stroke models, emphasizing the value of deep behavioral profiling in preclinical stroke research to enhance model validity for clinical translation.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141060215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-03DOI: 10.1177/0271678x241251570
Han Liu, Lin Meng, Jiuqi Wang, Chi Qin, Renyi Feng, Yongkang Chen, Pei Chen, Qingyong Zhu, Mingming Ma, Junfang Teng, Xuebing Ding
Perivascular spaces (PVSs) as the anatomical basis of the glymphatic system, are increasingly recognized as potential imaging biomarkers of neurological conditions. However, it is not clear whether enlarged PVSs are associated with alcohol-related brain damage (ARBD). We aimed to investigate the effect of long-term alcohol exposure on dyslipidemia and the glymphatic system in ARBD. We found that patients with ARBD exhibited significantly enlargement of PVSs in the frontal cortex and basal ganglia, as well as a notable increased levels of total cholesterol (TC) and triglycerides (TG). The anatomical changes of the glymphatic drainage system mentioned above were positively associated with TC and TG. To further explore whether enlarged PVSs affects the function of the glymphatic system in ARBD, we constructed long alcohol exposure and high fat diet mice models. The mouse model of long alcohol exposure exhibited increased levels of TC and TG, enlarged PVSs, the loss of aquaporin-4 polarity caused by reactive astrocytes and impaired glymphatic drainage function which ultimately caused cognitive deficits, in a similar way as high fat diet leading to impairment in glymphatic drainage. Our study highlights the contribution of dyslipidemia due to long-term alcohol abuse in the impairment of the glymphatic drainage system.
{"title":"Enlarged perivascular spaces in alcohol-related brain damage induced by dyslipidemia","authors":"Han Liu, Lin Meng, Jiuqi Wang, Chi Qin, Renyi Feng, Yongkang Chen, Pei Chen, Qingyong Zhu, Mingming Ma, Junfang Teng, Xuebing Ding","doi":"10.1177/0271678x241251570","DOIUrl":"https://doi.org/10.1177/0271678x241251570","url":null,"abstract":"Perivascular spaces (PVSs) as the anatomical basis of the glymphatic system, are increasingly recognized as potential imaging biomarkers of neurological conditions. However, it is not clear whether enlarged PVSs are associated with alcohol-related brain damage (ARBD). We aimed to investigate the effect of long-term alcohol exposure on dyslipidemia and the glymphatic system in ARBD. We found that patients with ARBD exhibited significantly enlargement of PVSs in the frontal cortex and basal ganglia, as well as a notable increased levels of total cholesterol (TC) and triglycerides (TG). The anatomical changes of the glymphatic drainage system mentioned above were positively associated with TC and TG. To further explore whether enlarged PVSs affects the function of the glymphatic system in ARBD, we constructed long alcohol exposure and high fat diet mice models. The mouse model of long alcohol exposure exhibited increased levels of TC and TG, enlarged PVSs, the loss of aquaporin-4 polarity caused by reactive astrocytes and impaired glymphatic drainage function which ultimately caused cognitive deficits, in a similar way as high fat diet leading to impairment in glymphatic drainage. Our study highlights the contribution of dyslipidemia due to long-term alcohol abuse in the impairment of the glymphatic drainage system.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1177/0271678x241249276
Kyriaki Kostoglou, Felipe Bello-Robles, Patrice Brassard, Max Chacon, Jurgen AHR Claassen, Marek Czosnyka, Jan-Willem Elting, Kun Hu, Lawrence Labrecque, Jia Liu, Vasilis Z Marmarelis, Stephen J Payne, Dae Cheol Shin, David Simpson, Jonathan Smirl, Ronney B Panerai, Georgios D Mitsis
Cerebral Autoregulation (CA) is an important physiological mechanism stabilizing cerebral blood flow (CBF) in response to changes in cerebral perfusion pressure (CPP). By maintaining an adequate, relatively constant supply of blood flow, CA plays a critical role in brain function. Quantifying CA under different physiological and pathological states is crucial for understanding its implications. This knowledge may serve as a foundation for informed clinical decision-making, particularly in cases where CA may become impaired. The quantification of CA functionality typically involves constructing models that capture the relationship between CPP (or arterial blood pressure) and experimental measures of CBF. Besides describing normal CA function, these models provide a means to detect possible deviations from the latter. In this context, a recent white paper from the Cerebrovascular Research Network focused on Transfer Function Analysis (TFA), which obtains frequency domain estimates of dynamic CA. In the present paper, we consider the use of time-domain techniques as an alternative approach. Due to their increased flexibility, time-domain methods enable the mitigation of measurement/physiological noise and the incorporation of nonlinearities and time variations in CA dynamics. Here, we provide practical recommendations and guidelines to support researchers and clinicians in effectively utilizing these techniques to study CA.
脑自动调节（CA）是一种重要的生理机制，可稳定脑血流（CBF）以应对脑灌注压（CPP）的变化。通过维持充足、相对恒定的血流供应，CA 在大脑功能中发挥着至关重要的作用。量化不同生理和病理状态下的 CA 对了解其影响至关重要。这些知识可作为临床决策的基础，尤其是在 CA 可能受损的情况下。CA 功能的量化通常涉及构建模型，以捕捉 CPP（或动脉血压）与 CBF 实验测量值之间的关系。除了描述正常的 CA 功能外，这些模型还提供了一种检测后者可能出现的偏差的方法。在此背景下，脑血管研究网络（Cerebrovascular Research Network）最近发布的一份白皮书重点介绍了传递函数分析（TFA），该方法可获得动态 CA 的频域估计值。在本文中，我们考虑使用时域技术作为替代方法。时域方法具有更高的灵活性，可以减轻测量/生理噪音，并将非线性和时间变化纳入 CA 动态分析。在此，我们将提供实用的建议和指南，以支持研究人员和临床医生有效利用这些技术来研究 CA。
{"title":"Time-domain methods for quantifying dynamic cerebral blood flow autoregulation: Review and recommendations. A white paper from the Cerebrovascular Research Network (CARNet)","authors":"Kyriaki Kostoglou, Felipe Bello-Robles, Patrice Brassard, Max Chacon, Jurgen AHR Claassen, Marek Czosnyka, Jan-Willem Elting, Kun Hu, Lawrence Labrecque, Jia Liu, Vasilis Z Marmarelis, Stephen J Payne, Dae Cheol Shin, David Simpson, Jonathan Smirl, Ronney B Panerai, Georgios D Mitsis","doi":"10.1177/0271678x241249276","DOIUrl":"https://doi.org/10.1177/0271678x241249276","url":null,"abstract":"Cerebral Autoregulation (CA) is an important physiological mechanism stabilizing cerebral blood flow (CBF) in response to changes in cerebral perfusion pressure (CPP). By maintaining an adequate, relatively constant supply of blood flow, CA plays a critical role in brain function. Quantifying CA under different physiological and pathological states is crucial for understanding its implications. This knowledge may serve as a foundation for informed clinical decision-making, particularly in cases where CA may become impaired. The quantification of CA functionality typically involves constructing models that capture the relationship between CPP (or arterial blood pressure) and experimental measures of CBF. Besides describing normal CA function, these models provide a means to detect possible deviations from the latter. In this context, a recent white paper from the Cerebrovascular Research Network focused on Transfer Function Analysis (TFA), which obtains frequency domain estimates of dynamic CA. In the present paper, we consider the use of time-domain techniques as an alternative approach. Due to their increased flexibility, time-domain methods enable the mitigation of measurement/physiological noise and the incorporation of nonlinearities and time variations in CA dynamics. Here, we provide practical recommendations and guidelines to support researchers and clinicians in effectively utilizing these techniques to study CA.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-29DOI: 10.1177/0271678x241239133
Tina Kroll, Alan Miranda, Alexandra Drechsel, Simone Beer, Markus Lang, Alexander Drzezga, Pedro Rosa-Neto, Jeroen Verhaeghe, David Elmenhorst, Andreas Bauer
To prevent motion artifacts in small animal positron emission tomography (PET), animals are routinely scanned under anesthesia or physical restraint. Both may potentially alter metabolism and neurochemistry. This study investigates the feasibility of fully awake acquisition and subsequent absolute quantification of dynamic brain PET data via pharmacokinetic modelling in moving rats using the glutamate 5 receptor radioligand [11C]ABP688 and point source based motion correction. Five male rats underwent three dynamic [11C]ABP688 PET scans: two test-retest awake PET scans and one scan under anesthesia for comparison. Specific radioligand binding was determined via the simplified reference tissue model (reference: cerebellum) and outcome parameters BPND and R1 were evaluated in terms of stability and reproducibility. Test-retest measurements in awake animals gave reliable results with high correlations of BPND (y = 1.08 × −0.2, r = 0.99, p < 0.01) and an acceptable variability (mean over all investigated regions 15.7 ± 2.4%). Regional [11C]ABP688 BPNDs under awake and anesthetized conditions were comparable although in awake scans, absolute radioactive peak uptakes were lower and relative blood flow in terms of R1 was higher. Awake small animal PET with absolute quantification of neuroreceptor availability is technically feasible and reproducible thereby providing a suitable alternative whenever effects of anesthesia are undesirable, e.g. in sleep research.
为防止小动物正电子发射断层扫描（PET）中出现运动伪影，动物通常在麻醉或身体束缚状态下进行扫描。这两种方法都有可能改变新陈代谢和神经化学。本研究利用谷氨酸 5 受体放射性配体 [11C]ABP688 和基于点源的运动校正，对移动大鼠进行完全清醒采集，并通过药代动力学模型对动态脑 PET 数据进行绝对量化。五只雄性大鼠接受了三次动态[11C]ABP688 PET 扫描：两次测试-重复清醒 PET 扫描和一次麻醉下扫描以进行比较。通过简化的参考组织模型（参考：小脑）确定了特定的放射性配体结合，并评估了结果参数 BPND 和 R1 的稳定性和可重复性。清醒动物的重测结果可靠，BPND 的相关性高（y = 1.08 × -0.2, r = 0.99, p < 0.01），变异性可接受（所有研究区域的平均值为 15.7 ± 2.4%）。清醒和麻醉条件下的区域[11C]ABP688 BPND 具有可比性，尽管在清醒扫描中，放射性峰值吸收的绝对值较低，R1 的相对血流量较高。对神经受体可用性进行绝对量化的清醒小动物正电子发射计算机断层扫描在技术上是可行的，而且具有可重复性，因此在不希望麻醉影响的情况下（如睡眠研究），它是一种合适的替代方法。
{"title":"Dynamic neuroreceptor positron emission tomography in non-anesthetized rats using point source based motion correction: A feasibility study with [11C]ABP688","authors":"Tina Kroll, Alan Miranda, Alexandra Drechsel, Simone Beer, Markus Lang, Alexander Drzezga, Pedro Rosa-Neto, Jeroen Verhaeghe, David Elmenhorst, Andreas Bauer","doi":"10.1177/0271678x241239133","DOIUrl":"https://doi.org/10.1177/0271678x241239133","url":null,"abstract":"To prevent motion artifacts in small animal positron emission tomography (PET), animals are routinely scanned under anesthesia or physical restraint. Both may potentially alter metabolism and neurochemistry. This study investigates the feasibility of fully awake acquisition and subsequent absolute quantification of dynamic brain PET data via pharmacokinetic modelling in moving rats using the glutamate 5 receptor radioligand [<jats:sup>11</jats:sup>C]ABP688 and point source based motion correction. Five male rats underwent three dynamic [<jats:sup>11</jats:sup>C]ABP688 PET scans: two test-retest awake PET scans and one scan under anesthesia for comparison. Specific radioligand binding was determined via the simplified reference tissue model (reference: cerebellum) and outcome parameters BP<jats:sub>ND</jats:sub> and R<jats:sub>1</jats:sub> were evaluated in terms of stability and reproducibility. Test-retest measurements in awake animals gave reliable results with high correlations of BP<jats:sub>ND</jats:sub> (y = 1.08 × −0.2, r = 0.99, p < 0.01) and an acceptable variability (mean over all investigated regions 15.7 ± 2.4%). Regional [<jats:sup>11</jats:sup>C]ABP688 BP<jats:sub>ND</jats:sub>s under awake and anesthetized conditions were comparable although in awake scans, absolute radioactive peak uptakes were lower and relative blood flow in terms of R<jats:sub>1</jats:sub> was higher. Awake small animal PET with absolute quantification of neuroreceptor availability is technically feasible and reproducible thereby providing a suitable alternative whenever effects of anesthesia are undesirable, e.g. in sleep research.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Blood-brain barrier (BBB) disruption is increasingly recognized as an early contributor to the pathophysiology of cerebral ischemia/reperfusion (I/R) injury, and is also a key event in triggering secondary damage to the central nervous system. Recently, long non-coding RNA (lncRNA) have been found to be associated with ischemic stroke. However, the roles of lncRNA in BBB homeostasis remain largely unknown. Here, we report that long intergenic non-coding RNA-p21 (lincRNA-p21) was the most significantly down-regulated lncRNA in human brain microvascular endothelial cells (HBMECs) after oxygen and glucose deprivation/reoxygenation (OGD/R) treatment among candidate lncRNA, which were both sensitive to hypoxia and involved in atherosclerosis. Exogenous brain-endothelium-specific overexpression of lincRNA-p21 could alleviate BBB disruption, diminish infarction volume and attenuate motor function deficits in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. Further results showed that lincRNA-p21 was critical to maintain BBB integrity by inhibiting the degradation of junction proteins under MCAO/R and OGD/R conditions. Specifically, lincRNA-p21 could inhibit autophagy-dependent degradation of occludin by activating PI3K/AKT/mTOR signaling pathway. Besides, lincRNA-p21 could inhibit VE-cadherin degradation by binding with miR-101-3p. Together, we identify that lincRNA-p21 is critical for BBB integrity maintenance, and endothelial lincRNA-p21 overexpression could alleviate cerebral I/R injury in mice, pointing to a potential strategy to treat cerebral I/R injury.
{"title":"Endothelial lincRNA-p21 alleviates cerebral ischemia/reperfusion injury by maintaining blood-brain barrier integrity","authors":"Yun-Hua Zhao, Yu Liang, Kang-Ji Wang, Sheng-Nan Jin, Xiao-Meng Yu, Qian Zhang, Jia-Yi Wei, Hui Liu, Wen-Gang Fang, Wei-Dong Zhao, Yuan Li, Yu-Hua Chen","doi":"10.1177/0271678x241248907","DOIUrl":"https://doi.org/10.1177/0271678x241248907","url":null,"abstract":"Blood-brain barrier (BBB) disruption is increasingly recognized as an early contributor to the pathophysiology of cerebral ischemia/reperfusion (I/R) injury, and is also a key event in triggering secondary damage to the central nervous system. Recently, long non-coding RNA (lncRNA) have been found to be associated with ischemic stroke. However, the roles of lncRNA in BBB homeostasis remain largely unknown. Here, we report that long intergenic non-coding RNA-p21 (lincRNA-p21) was the most significantly down-regulated lncRNA in human brain microvascular endothelial cells (HBMECs) after oxygen and glucose deprivation/reoxygenation (OGD/R) treatment among candidate lncRNA, which were both sensitive to hypoxia and involved in atherosclerosis. Exogenous brain-endothelium-specific overexpression of lincRNA-p21 could alleviate BBB disruption, diminish infarction volume and attenuate motor function deficits in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. Further results showed that lincRNA-p21 was critical to maintain BBB integrity by inhibiting the degradation of junction proteins under MCAO/R and OGD/R conditions. Specifically, lincRNA-p21 could inhibit autophagy-dependent degradation of occludin by activating PI3K/AKT/mTOR signaling pathway. Besides, lincRNA-p21 could inhibit VE-cadherin degradation by binding with miR-101-3p. Together, we identify that lincRNA-p21 is critical for BBB integrity maintenance, and endothelial lincRNA-p21 overexpression could alleviate cerebral I/R injury in mice, pointing to a potential strategy to treat cerebral I/R injury.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140798079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-19DOI: 10.1177/0271678x241227022
Jonah Gordon, Cesar V Borlongan
With a foundation built upon initial work from the 1980s demonstrating graft viability in cerebral ischemia, stem cell transplantation has shown immense promise in promoting survival, enhancing neuroprotection and inducing neuroregeneration, while mitigating both histological and behavioral deficits that frequently accompany ischemic stroke. These findings have led to a number of clinical trials that have thoroughly supported a strong safety profile for stem cell therapy in patients but have generated variable efficacy. As preclinical evidence continues to expand through the investigation of new cell lines and optimization of stem cell delivery, it remains critical for translational models to adhere to the protocols established through basic scientific research. With the recent shift in approach towards utilization of stem cells as a conjunctive therapy alongside standard thrombolytic treatments, key issues including timing, route of administration, and stem cell type must each be appropriately translated from the laboratory in order to resolve the question of stem cell efficacy for cerebral ischemia that ultimately will enhance therapeutics for stroke patients towards improving quality of life.
{"title":"An update on stem cell therapy for stroke patients: Where are we now?","authors":"Jonah Gordon, Cesar V Borlongan","doi":"10.1177/0271678x241227022","DOIUrl":"https://doi.org/10.1177/0271678x241227022","url":null,"abstract":"With a foundation built upon initial work from the 1980s demonstrating graft viability in cerebral ischemia, stem cell transplantation has shown immense promise in promoting survival, enhancing neuroprotection and inducing neuroregeneration, while mitigating both histological and behavioral deficits that frequently accompany ischemic stroke. These findings have led to a number of clinical trials that have thoroughly supported a strong safety profile for stem cell therapy in patients but have generated variable efficacy. As preclinical evidence continues to expand through the investigation of new cell lines and optimization of stem cell delivery, it remains critical for translational models to adhere to the protocols established through basic scientific research. With the recent shift in approach towards utilization of stem cells as a conjunctive therapy alongside standard thrombolytic treatments, key issues including timing, route of administration, and stem cell type must each be appropriately translated from the laboratory in order to resolve the question of stem cell efficacy for cerebral ischemia that ultimately will enhance therapeutics for stroke patients towards improving quality of life.","PeriodicalId":15356,"journal":{"name":"Journal of Cerebral Blood Flow & Metabolism","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140630543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：