1
|
Yang C, Wang Y, Wu X, Gong M, Li Y. Reduced levels of A20 protein prompted RIPK1-dependent apoptosis and blood-brain barrier breakdown during cerebral ischemia reperfusion injury. PLoS One 2023; 18:e0290015. [PMID: 37578944 PMCID: PMC10424866 DOI: 10.1371/journal.pone.0290015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 08/01/2023] [Indexed: 08/16/2023] Open
Abstract
Blood-brain barrier (BBB) leakage is an important cause of the exacerbation of pathological features of cerebral ischemia reperfusion injury (CIRI). However, the specific mechanism of BBB leakage is not clear. It was found that the CIRI resulted in RIPK1 activation and subsequent RIPK1-dependent apoptosis (RDA). Inhibition of RIPK1 significantly reduced BBB breakdown and brain damage. The aim of this study is to investigate the mechanism of RIPK1 in the BBB leakage during CIRI. It was discovered by proteomics that autophagy activation resulting from ischemia and reperfusion significantly downregulated the level of A20 protein. A20 is an important protein that regulates RIPK1 and RDA. It was hypothesized that activation of autophagy caused by ischemic reperfusion led to a decrease in A20 protein, which, in turn, caused the activation of RIPK1 and the occurrence of RDA, leading to leakage of the BBB. The findings in this study revealed the role of RIPK1 in the cell death and BBB leakage upon cerebral ischemia reperfusion injury, and these findings provide a novel perspective for the treatment of ischemic reperfusion.
Collapse
Affiliation(s)
- Chaonan Yang
- Department of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Yongjiao Wang
- Department of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Xiaohui Wu
- Department of Pharmacy, Tianjin Medical University, Tianjin, China
| | - Min Gong
- Department of Pharmacy, Tianjin Medical University, Tianjin, China
- WIMM, University of Oxford, Oxford, United Kingdom
| | - Ying Li
- Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China
| |
Collapse
|
2
|
Fuhs T, Flachmeyer B, Krueger M, Blietz A, Härtig W, Michalski D. Combining atomic force microscopy and fluorescence-based techniques to explore mechanical properties of naive and ischemia-affected brain regions in mice. Sci Rep 2023; 13:12774. [PMID: 37550347 PMCID: PMC10406906 DOI: 10.1038/s41598-023-39277-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 07/22/2023] [Indexed: 08/09/2023] Open
Abstract
Knowledge of the brain's structure and function is essential for understanding processes in health and disease. Histochemical and fluorescence-based techniques have proven beneficial in characterizing brain regions and cellular compositions in pre-clinical research. Atomic force microscopy (AFM) has been introduced for mechanical tissue characterization, which may also help investigate pathophysiological aspects in disease-related models such as stroke. While combining AFM and fluorescence-based techniques, this study explored the mechanical properties of naive and ischemic brain regions in mice. Ischemia-affected regions were identified by the green signal of fluorescein isothiocyanate-conjugated albumin. A semi-automated protocol based on a brain atlas allowed regional allocations to the neocortex, striatum, thalamus, hypothalamus, hippocampus, and fiber tracts. Although AFM led to varying measurements, intra-individual analyses indicated a gradually increased tissue stiffness in the neocortex compared to subcortical areas, i.e., the striatum and fiber tracts. Regions affected by ischemia predominantly exhibited an increased tissue stiffness compared to those of the contra-lateral hemisphere, which might be related to cellular swelling. This study indicated intra-individual differences in mechanical properties among naive and ischemia-affected brain regions. The combination of AFM, semi-automated regional allocations, and fluorescence-based techniques thus qualifies for mechanical characterizations of the healthy and disease-affected brain in pre-clinical research.
Collapse
Affiliation(s)
- Thomas Fuhs
- Section of Soft Matter Physics, Faculty of Physics and Geosciences, University of Leipzig, Linnéstr. 5, 04103, Leipzig, Germany
- Institute for Physical Chemistry, Faculty of Chemistry and Physics, Technical University Freiberg, Leipziger Str. 29, 09599, Freiberg, Germany
| | - Bianca Flachmeyer
- Institute of Anatomy, Medical Faculty, University of Leipzig, Liebigstr. 13, 04103, Leipzig, Germany
| | - Martin Krueger
- Institute of Anatomy, Medical Faculty, University of Leipzig, Liebigstr. 13, 04103, Leipzig, Germany
| | - Alexandra Blietz
- Department of Neurology, Medical Faculty, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany
| | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, Medical Faculty, University of Leipzig, Liebigstr. 19, 04103, Leipzig, Germany
| | - Dominik Michalski
- Department of Neurology, Medical Faculty, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany.
| |
Collapse
|
3
|
Höfling C, Roßner S, Flachmeyer B, Krueger M, Härtig W, Michalski D. Tricellulin, α-Catenin and Microfibrillar-Associated Protein 5 Exhibit Concomitantly Altered Immunosignals along with Vascular, Extracellular and Cytoskeletal Elements after Experimental Focal Cerebral Ischemia. Int J Mol Sci 2023; 24:11893. [PMID: 37569268 PMCID: PMC10418498 DOI: 10.3390/ijms241511893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/08/2023] [Accepted: 07/21/2023] [Indexed: 08/13/2023] Open
Abstract
Along with initiatives to understand the pathophysiology of stroke in detail and to identify neuroprotective targets, cell-stabilizing elements have gained increasing attention. Although cell culture experiments have indicated that tricellulin, α-catenin and microfibrillar-associated protein 5 (MFAP5) contribute to cellular integrity, these elements have not yet been investigated in the ischemic brain. Applying immunofluorescence labeling, this study explored tricellulin, MFAP5 and α-catenin in non-ischemic and ischemic brain areas of mice (24, 4 h of ischemia) and rats (4 h of ischemia), along with collagen IV and fibronectin as vascular and extracellular matrix constituents and microtubule-associated protein 2 (MAP2) and neurofilament light chain (NF-L) as cytoskeletal elements. Immunosignals of tricellulin and notably MFAP5 partially appeared in a fiber-like pattern, and α-catenin appeared more in a dotted pattern. Regional associations with vascular and extracellular constituents were found for tricellulin and α-catenin, particularly in ischemic areas. Due to ischemia, signals of tricellulin, MFAP5 and α-catenin decreased concomitantly with MAP2 and NF-L, whereby MFAP5 provided the most sensitive reaction. For the first time, this study demonstrated ischemia-related alterations in tricellulin, MFAP5 and α-catenin along with the vasculature, extracellular matrix and cytoskeleton. Confirmatory studies are needed, also exploring their role in cellular integrity and the potential for neuroprotective approaches in stroke.
Collapse
Affiliation(s)
- Corinna Höfling
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (C.H.); (S.R.); (W.H.)
| | - Steffen Roßner
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (C.H.); (S.R.); (W.H.)
| | - Bianca Flachmeyer
- Institute of Anatomy, University of Leipzig, Liebigstr. 13, 04103 Leipzig, Germany; (B.F.); (M.K.)
| | - Martin Krueger
- Institute of Anatomy, University of Leipzig, Liebigstr. 13, 04103 Leipzig, Germany; (B.F.); (M.K.)
| | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (C.H.); (S.R.); (W.H.)
| | - Dominik Michalski
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103 Leipzig, Germany
| |
Collapse
|
4
|
Michalski D, Reimann W, Spielvogel E, Mages B, Biedermann B, Barthel H, Nitzsche B, Schob S, Härtig W. Regionally Altered Immunosignals of Surfactant Protein-G, Vascular and Non-Vascular Elements of the Neurovascular Unit after Experimental Focal Cerebral Ischemia in Mice, Rats, and Sheep. Int J Mol Sci 2022; 23:ijms23115875. [PMID: 35682557 PMCID: PMC9180438 DOI: 10.3390/ijms23115875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/14/2022] [Accepted: 05/19/2022] [Indexed: 01/12/2023] Open
Abstract
The surfactant protein-G (SP-G) has recently been discovered in the brain and linked to fluid balance regulations. Stroke is characterized by impaired vessel integrity, promoting water influx and edema formation. The neurovascular unit concept (NVU) has been generated to cover not only ischemic affections of neurons or vessels but also other regionally associated cells. This study provides the first spatio-temporal characterization of SP-G and NVU elements after experimental stroke. Immunofluorescence labeling was applied to explore SP-G, vascular and cellular markers in mice (4, 24, and 72 h of ischemia), rats (24 h of ischemia), and sheep (two weeks of ischemia). Extravasated albumin indicated vascular damage within ischemic areas. Quantifications revealed decreasing SP-G signals in the ischemia-affected neocortex and subcortex. Inverse immunosignals of SP-G and vascular elements existed throughout all models. Despite local associations between SP-G and the vasculature, a definite co-localization was not seen. Along with a decreased SP-G-immunoreactivity in ischemic areas, signals originating from neurons, glial elements, and the extracellular matrix exhibited morphological alterations or changed intensities. Collectively, this study revealed regional alterations of SP-G, vascular, and non-vascular NVU elements after ischemia, and may thus stimulate the discussion about the role of SP-G during stroke.
Collapse
Affiliation(s)
- Dominik Michalski
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103 Leipzig, Germany; (W.R.); (E.S.)
- Correspondence: ; Tel.: +49-341-9724339
| | - Willi Reimann
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103 Leipzig, Germany; (W.R.); (E.S.)
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (B.B.); (W.H.)
| | - Emma Spielvogel
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103 Leipzig, Germany; (W.R.); (E.S.)
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (B.B.); (W.H.)
| | - Bianca Mages
- Institute of Anatomy, University of Leipzig, Liebigstr. 13, 04103 Leipzig, Germany;
| | - Bernd Biedermann
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (B.B.); (W.H.)
| | - Henryk Barthel
- Department of Nuclear Medicine, University of Leipzig, Stephanstr. 11, 04103 Leipzig, Germany; (H.B.); (B.N.)
| | - Björn Nitzsche
- Department of Nuclear Medicine, University of Leipzig, Stephanstr. 11, 04103 Leipzig, Germany; (H.B.); (B.N.)
- Institute of Anatomy, Histology, and Embryology, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 43, 04103 Leipzig, Germany
| | - Stefan Schob
- Department of Neuroradiology, University of Halle, Ernst-Grube-Str. 40, 06120 Halle (Saale), Germany;
| | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; (B.B.); (W.H.)
| |
Collapse
|
5
|
Härtig W, Meinicke A, Michalski D, Schob S, Jäger C. Update on Perineuronal Net Staining With Wisteria floribunda Agglutinin (WFA). Front Integr Neurosci 2022; 16:851988. [PMID: 35431825 PMCID: PMC9011100 DOI: 10.3389/fnint.2022.851988] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/02/2022] [Indexed: 11/13/2022] Open
Abstract
As chemically specialized forms of the extracellular matrix in the central nervous system, polyanionic perineuronal nets (PNs) contain diverse constituents, including chondroitin sulfate proteoglycans (CSPGs), hyaluronic acid, and tenascins. They are detectable by various histological approaches such as colloidal iron binding and immunohistochemical staining to reveal, for instance, the CSPGs aggrecan, neurocan, phosphacan, and versican. Moreover, biotin, peroxidase, or fluorescein conjugates of the lectins Vicia villosa agglutinin and soybean agglutinin enable the visualization of PNs. At present, the N-acetylgalactosamine-binding Wisteria floribunda agglutinin (WFA) is the most widely applied marker for PNs. Therefore, this article is largely focused on methodological aspects of WFA staining. Notably, fluorescent WFA labeling allows, after its conversion into electron-dense adducts, electron microscopic analyses. Furthermore, the usefulness of WFA conjugates for the oftentimes neglected in vivo and in vitro labeling of PNs is emphasized. Subsequently, we discuss impaired WFA-staining sites after long-lasting experiments in vitro, especially in autoptic brain samples with long postmortem delay and partial enzymatic degradation, while immunolabeling of aggrecan and CSPG link proteins under such conditions has proven more robust. In some hippocampal regions from perfusion-fixed mice, more PNs are aggrecan immunoreactive than WFA positive, whereas the retrosplenial cortex displays many WFA-binding PNs devoid of visible aggrecan immunoreactivity. Additional multiple fluorescence labeling exemplarily revealed in ischemic tissue diminished staining of WFA-binding sites and aquaporin 4 and concomitantly upregulated immunolabeling of neurofilament, light chains, and collagen IV. Finally, we briefly discuss possible future staining approaches based on nanobodies to facilitate novel technologies revealing details of net morphology.
Collapse
Affiliation(s)
- Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
- *Correspondence: Wolfgang Härtig,
| | - Anton Meinicke
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | | | - Stefan Schob
- Department of Neuroradiology, Clinic and Policlinic of Radiology, University Hospital Halle, Halle (Saale), Germany
| | - Carsten Jäger
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| |
Collapse
|
6
|
Lee TK, Lee JC, Kim JD, Kim DW, Ahn JH, Park JH, Kim HI, Cho JH, Choi SY, Won MH, Kang IIJ. Populus tomentiglandulosa Extract Is Rich in Polyphenols and Protects Neurons, Astrocytes, and the Blood-Brain Barrier in Gerbil Striatum Following Ischemia-Reperfusion Injury. Molecules 2021; 26:5430. [PMID: 34576901 PMCID: PMC8471727 DOI: 10.3390/molecules26185430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 12/19/2022] Open
Abstract
Transient ischemia in brains causes neuronal damage, gliosis, and blood-brain barrier (BBB) breakdown, which is related to ischemia-induced brain dysfunction. Populus species have various pharmacological properties including antioxidant and anti-inflammatory activities. In this study, we found that phenolic compounds were rich in Populus tomentiglandulosa extract and examined the effects of Populus tomentiglandulosa extract on neuronal damage/death, astrogliosis, and BBB breakdown in the striatum, which is related to motor behavior, following 15-min transient ischemia in the forebrain in gerbils. The gerbils were pre-treated with 50, 100, and 200 mg/kg of the extract. The latter showed significant effects against ischemia-reperfusion injury. Ischemia-induced hyperactivity using spontaneous motor activity test was significantly attenuated by the treatment. Striatal cells (neurons) were dead at five days after the ischemia; however, pre-treatment with the extract protected the striatal cells from ischemia/reperfusion injury. Ischemia-induced reactive astrogliosis was significantly alleviated, in particular, astrocyte end feet, which are a component of BBB, were significantly preserved. Immunoglobulin G, which is not found in intact brain parenchyma, was apparently shown (an indicator of extravasation) in striatal parenchyma at five days after the ischemia, but IgG leakage was dramatically attenuated in the parenchyma by the pre-treatment. Based on these findings, we suggest that Populus tomentiglandulosa extract rich in phenolic compounds can be employed as a pharmaceutical composition to develop a preventive material against brain ischemic injury.
Collapse
Affiliation(s)
- Tae-Kyeong Lee
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Gangwon, Korea; (T.-K.L.); (S.-Y.C.)
| | - Jae-Chul Lee
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 24341, Gangwon, Korea; (J.-C.L.); (J.-H.A.)
| | - Jong-Dai Kim
- Division of Food Biotechnology, School of Biotechnology, Kangwon National University, Chuncheon 24341, Gangwon, Korea;
| | - Dae-Won Kim
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangnung–Wonju National University, Gangneung 25457, Gangwon, Korea;
| | - Ji-Hyeon Ahn
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 24341, Gangwon, Korea; (J.-C.L.); (J.-H.A.)
- Department of Physical Therapy, College of Health Science, Youngsan University, Yangsan 50510, Gyeongsangnam, Korea
| | - Joon-Ha Park
- Department of Anatomy, College of Korean Medicine, Dongguk University, Gyeongju 38066, North Gyeongsang, Korea;
| | - Hyung-Il Kim
- Department of Emergency Medicine, Dankook University Hospital, College of Medicine, Dankook University, Cheonan 31116, Chungnam, Korea;
- Department of Emergency Medicine, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon 24289, Gangwon, Korea;
| | - Jun-Hwi Cho
- Department of Emergency Medicine, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon 24289, Gangwon, Korea;
| | - Soo-Young Choi
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Gangwon, Korea; (T.-K.L.); (S.-Y.C.)
| | - Moo-Ho Won
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 24341, Gangwon, Korea; (J.-C.L.); (J.-H.A.)
| | - II-Jun Kang
- Department of Food Science and Nutrition, Hallym University, Chuncheon 24252, Gangwon, Korea
| |
Collapse
|
7
|
Mages B, Fuhs T, Aleithe S, Blietz A, Hobusch C, Härtig W, Schob S, Krueger M, Michalski D. The Cytoskeletal Elements MAP2 and NF-L Show Substantial Alterations in Different Stroke Models While Elevated Serum Levels Highlight Especially MAP2 as a Sensitive Biomarker in Stroke Patients. Mol Neurobiol 2021; 58:4051-4069. [PMID: 33931805 PMCID: PMC8280005 DOI: 10.1007/s12035-021-02372-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 03/22/2021] [Indexed: 02/07/2023]
Abstract
In the setting of ischemic stroke, the neurofilament subunit NF-L and the microtubule-associated protein MAP2 have proven to be exceptionally ischemia-sensitive elements of the neuronal cytoskeleton. Since alterations of the cytoskeleton have been linked to the transition from reversible to irreversible tissue damage, the present study investigates underlying time- and region-specific alterations of NF-L and MAP2 in different animal models of focal cerebral ischemia. Although NF-L is increasingly established as a clinical stroke biomarker, MAP2 serum measurements after stroke are still lacking. Therefore, the present study further compares serum levels of MAP2 with NF-L in stroke patients. In the applied animal models, MAP2-related immunofluorescence intensities were decreased in ischemic areas, whereas the abundance of NF-L degradation products accounted for an increase of NF-L-related immunofluorescence intensity. Accordingly, Western blot analyses of ischemic areas revealed decreased protein levels of both MAP2 and NF-L. The cytoskeletal alterations are further reflected at an ultrastructural level as indicated by a significant reduction of detectable neurofilaments in cortical axons of ischemia-affected areas. Moreover, atomic force microscopy measurements confirmed altered mechanical properties as indicated by a decreased elastic strength in ischemia-affected tissue. In addition to the results from the animal models, stroke patients exhibited significantly elevated serum levels of MAP2, which increased with infarct size, whereas serum levels of NF-L did not differ significantly. Thus, MAP2 appears to be a more sensitive stroke biomarker than NF-L, especially for early neuronal damage. This perspective is strengthened by the results from the animal models, showing MAP2-related alterations at earlier time points compared to NF-L. The profound ischemia-induced alterations further qualify both cytoskeletal elements as promising targets for neuroprotective therapies.
Collapse
Affiliation(s)
- Bianca Mages
- Institute of Anatomy, Leipzig University, Leipzig, Germany.
| | - Thomas Fuhs
- Section of Soft Matter Physics, Faculty of Physics and Geosciences, Leipzig University, Leipzig, Germany
| | - Susanne Aleithe
- Department of Neurology, Leipzig University, Leipzig, Germany
| | | | | | - Wolfgang Härtig
- Paul Flechsig Institute of Brain Research, Leipzig University, Leipzig, Germany
| | - Stefan Schob
- Department of Neuroradiology, Leipzig University, Leipzig, Germany
| | - Martin Krueger
- Institute of Anatomy, Leipzig University, Leipzig, Germany
| | | |
Collapse
|
8
|
Lee CH, Ahn JH, Lee TK, Sim H, Lee JC, Park JH, Shin MC, Cho JH, Kim DW, Won MH, Choi SY. Comparison of Neuronal Death, Blood-Brain Barrier Leakage and Inflammatory Cytokine Expression in the Hippocampal CA1 Region Following Mild and Severe Transient Forebrain Ischemia in Gerbils. Neurochem Res 2021; 46:2852-2866. [PMID: 34050880 DOI: 10.1007/s11064-021-03362-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/13/2021] [Accepted: 05/24/2021] [Indexed: 11/25/2022]
Abstract
Transient ischemia in the brain causes blood-brain barrier (BBB) breakdown and dysfunction, which is related to ischemia-induced neuronal damage. Leakage of plasma proteins following transient ischemia is one of the indicators that is used to determine the extent of BBB dysfunction. In this study, neuronal damage/death, leakage of albumin and IgG, microgliosis, and inflammatory cytokine expression were examined in the hippocampal CA1 region, which is vulnerable to transient ischemia, following 5-min (mild) and 15-min (severe) ischemia in gerbils induced by transient common carotid arteries occlusion (tCCAo). tCCAo-induced neuronal damage/death occurred earlier and was more severe after 15-min tCCAo vs. after 5-min tCCAo. Significant albumin and IgG leakage (albumin and IgG immunoreactivity) took 1 or 2 days to begin, and immunoreactivity was markedly increased 5 days after 5-min tCCAo. While, albumin and IgG leakage began to increase 6 h after 15-min tCCAo and remained significantly higher over time than that seen in 5-min tCCAo. IgG immunoreactivity was observed in degenerating neurons and activated microglia after tCCAo, and microglia were activated to a greater extent after 15-min tCCAo than 5-min tCCAo. In addition, following 15-min tCCAo, pro-inflammatory cytokines [tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β)] immunoreactivity was significantly higher than that seen following 5-min tCCAo, whereas immunoreactivity of anti-inflammatory cytokines (IL-4 and IL-13) was lower in 15-min than 5-min tCCAo. These results indicate that duration of tCCAo differentially affects the timing and degree of neuronal damage or loss, albumin and IgG leakage and inflammatory cytokine expression in brain tissue. In addition, more severe BBB leakage is closely related to acceleration of neuronal damage through increased microglial activation and pro-inflammatory cytokine expression in the ischemic hippocampal CA1 region.
Collapse
Affiliation(s)
- Choong-Hyun Lee
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, Chungnam, 31116, Republic of Korea
| | - Ji Hyeon Ahn
- Department of Physical Therapy, College of Health Science, Youngsan University, Yangsan, Gyeongnam, 50510, Republic of Korea
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Tae-Kyeong Lee
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon, 24252, Republic of Korea
| | - Hyejin Sim
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Jae-Chul Lee
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Joon Ha Park
- Department of Anatomy, College of Korean Medicine, Dongguk University, Gyeongju, Gyeongbuk, 38066, Republic of Korea
| | - Myoung Cheol Shin
- Department of Emergency Medicine, School of Medicine, Kangwon National University Hospital, Kangwon National University, Chuncheon, Gangwon, 24289, Republic of Korea
| | - Jun Hwi Cho
- Department of Emergency Medicine, School of Medicine, Kangwon National University Hospital, Kangwon National University, Chuncheon, Gangwon, 24289, Republic of Korea
| | - Dae Won Kim
- Department of Biochemistry and Molecular Biology, and Research Institute of Oral Sciences, College of Dentistry, Gangnung-Wonju National University, Gangneung, Gangwon, 25457, Republic of Korea
| | - Moo-Ho Won
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea.
| | - Soo Young Choi
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon, 24252, Republic of Korea.
| |
Collapse
|
9
|
Ye D, Luan J, Pang H, Yang Y, Nazeri A, Rubin JB, Chen H. Characterization of focused ultrasound-mediated brainstem delivery of intranasally administered agents. J Control Release 2020; 328:276-285. [PMID: 32871204 PMCID: PMC7749082 DOI: 10.1016/j.jconrel.2020.08.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022]
Abstract
Focused ultrasound-mediated intranasal (FUSIN) delivery is a recently proposed technique that bypasses the blood-brain barrier to achieve noninvasive and localized brain drug delivery. The goal of this study was to characterize FUSIN drug delivery outcome in mice with regard to its dependency on several critical experimental factors, including the time interval between IN administration and FUS sonication (Tlag1), the FUS pressure, and the time for sacrificing the mice post-FUS (Tlag2). Wild-type mice were treated by FUSIN delivery of near-infrared fluorescent dye-labeled bovine serum albumin (800CW-BSA, used as a model agent). 800CW-BSA was intranasally administered to the mice in vivo, followed by intravenous injection of microbubbles and FUS sonication at the brainstem. Fluorescence imaging of ex vivo mouse brain slices was used to quantify the delivery outcomes of 800CW-BSA. Major organs, along with the nasal tissue and trigeminal nerve, were harvested to assess the biodistribution of 800CW-BSA. The delivery outcome of 800CW-BSA was the highest at the brainstem when Tlag1 was 0.5 h, which was on average 24.5-fold, 5.4-fold, and 21.6-fold higher than those of the IN only, Tlag1 = 1.5 h, and Tlag1 = 4.0 h, respectively. The FUSIN delivery outcome at the lowest pressure level, 0.43 MPa, was on average 1.8-fold and 3.7-fold higher than those at 0.56 MPa and 0.70 MPa, respectively. The mean concentration of 800CW-BSA in the brainstem after FUSIN delivery decreased from 0.5 h to 4.0 h post-FUS. The accumulation of 800CW-BSA was low in the heart, lung, spleen, kidneys, and liver, but high in the stomach and intestines. This study revealed the unique characteristics of FUSIN as a noninvasive, efficient, and localized brain drug delivery technique.
Collapse
Affiliation(s)
- Dezhuang Ye
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Saint Louis, MO, 63130, USA
| | - Jingyi Luan
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Saint Louis, MO, 63130, USA
| | - Hannah Pang
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO, 63130, USA
| | - Yaoheng Yang
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO, 63130, USA
| | - Arash Nazeri
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO., 63110, USA
| | - Joshua B Rubin
- Departments of Pediatrics and Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Hong Chen
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO, 63130, USA; Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, MO, 63108, USA..
| |
Collapse
|
10
|
Michalski D, Spielvogel E, Puchta J, Reimann W, Barthel H, Nitzsche B, Mages B, Jäger C, Martens H, Horn AKE, Schob S, Härtig W. Increased Immunosignals of Collagen IV and Fibronectin Indicate Ischemic Consequences for the Neurovascular Matrix Adhesion Zone in Various Animal Models and Human Stroke Tissue. Front Physiol 2020; 11:575598. [PMID: 33192578 PMCID: PMC7649770 DOI: 10.3389/fphys.2020.575598] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 09/23/2020] [Indexed: 12/21/2022] Open
Abstract
Ischemic stroke causes cellular alterations in the “neurovascular unit” (NVU) comprising neurons, glia, and the vasculature, and affects the blood-brain barrier (BBB) with adjacent extracellular matrix (ECM). Limited data are available for the zone between the NVU and ECM that has not yet considered for neuroprotective approaches. This study describes ischemia-induced alterations for two main components of the neurovascular matrix adhesion zone (NMZ), i.e., collagen IV as basement membrane constituent and fibronectin as crucial part of the ECM, in conjunction with traditional NVU elements. For spatio-temporal characterization of these structures, multiple immunofluorescence labeling was applied to tissues affected by focal cerebral ischemia using a filament-based model in mice (4, 24, and 72 h of ischemia), a thromboembolic model in rats (24 h of ischemia), a coagulation-based model in sheep (2 weeks of ischemia), and human autoptic stroke tissue (3 weeks of ischemia). An increased fibronectin immunofluorescence signal demarcated ischemia-affected areas in mice, along with an increased collagen IV signal and BBB impairment indicated by serum albumin extravasation. Quantifications revealed a region-specific pattern with highest collagen IV and fibronectin intensities in most severely affected neocortical areas, followed by a gradual decline toward the border zone and non-affected regions. Comparing 4 and 24 h of ischemia, the subcortical fibronectin signal increased significantly over time, whereas neocortical areas displayed only a gradual increase. Qualitative analyses confirmed increased fibronectin and collagen IV signals in ischemic areas from all tissues and time points investigated. While the increased collagen IV signal was restricted to vessels, fibronectin appeared diffusely arranged in the parenchyma with focal accumulations associated to the vasculature. Integrin α5 appeared enriched in the vicinity of fibronectin and vascular elements, while most of the non-vascular NVU elements showed complementary staining patterns referring to fibronectin. This spatio-temporal characterization of ischemia-related alterations of collagen IV and fibronectin in various stroke models and human autoptic tissue shows that ischemic consequences are not limited to traditional NVU components and the ECM, but also involve the NMZ. Future research should explore more components and the pathophysiological properties of the NMZ as a possible target for novel neuroprotective approaches.
Collapse
Affiliation(s)
| | - Emma Spielvogel
- Department of Neurology, University of Leipzig, Leipzig, Germany.,Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Joana Puchta
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany.,Department of Neuroradiology, University of Leipzig, Leipzig, Germany
| | - Willi Reimann
- Department of Neurology, University of Leipzig, Leipzig, Germany.,Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Henryk Barthel
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Björn Nitzsche
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany.,Institute of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
| | - Bianca Mages
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Carsten Jäger
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | | | - Anja K E Horn
- Institute of Anatomy and Cell Biology I and German Center for Vertigo and Balance Disorders, Ludwig-Maximilians-University, Munich, Germany
| | - Stefan Schob
- Department of Neuroradiology, University of Leipzig, Leipzig, Germany
| | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| |
Collapse
|
11
|
Wu Y, Wu H, Guo X, Pluimer B, Zhao Z. Blood-Brain Barrier Dysfunction in Mild Traumatic Brain Injury: Evidence From Preclinical Murine Models. Front Physiol 2020; 11:1030. [PMID: 32973558 PMCID: PMC7472692 DOI: 10.3389/fphys.2020.01030] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 07/28/2020] [Indexed: 12/11/2022] Open
Abstract
Mild traumatic brain injury (mTBI) represents more than 80% of total TBI cases and is a robust environmental risk factor for neurodegenerative diseases including Alzheimer’s disease (AD). Besides direct neuronal injury and neuroinflammation, blood–brain barrier (BBB) dysfunction is also a hallmark event of the pathological cascades after mTBI. However, the vascular link between BBB impairment caused by mTBI and subsequent neurodegeneration remains undefined. In this review, we focus on the preclinical evidence from murine models of BBB dysfunction in mTBI and provide potential mechanistic links between BBB disruption and the development of neurodegenerative diseases.
Collapse
Affiliation(s)
- Yingxi Wu
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Haijian Wu
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States.,Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xinying Guo
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Brock Pluimer
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States.,Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Zhen Zhao
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States.,Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
12
|
Rust R, Kirabali T, Grönnert L, Dogancay B, Limasale YDP, Meinhardt A, Werner C, Laviña B, Kulic L, Nitsch RM, Tackenberg C, Schwab ME. A Practical Guide to the Automated Analysis of Vascular Growth, Maturation and Injury in the Brain. Front Neurosci 2020; 14:244. [PMID: 32265643 PMCID: PMC7099171 DOI: 10.3389/fnins.2020.00244] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/04/2020] [Indexed: 12/15/2022] Open
Abstract
The distinct organization of the brain's vasculature ensures the adequate delivery of oxygen and nutrients during development and adulthood. Acute and chronic pathological changes of the vascular system have been implicated in many neurological disorders including stroke and dementia. Here, we describe a fast, automated method that allows the highly reproducible, quantitative assessment of distinct vascular parameters and their changes based on the open source software Fiji (ImageJ). In particular, we developed a practical guide to reliably measure aspects of growth, repair and maturation of the brain's vasculature during development and neurovascular disease in mice and humans. The script can be used to assess the effects of different external factors including pharmacological treatments or disease states. Moreover, the procedure is expandable to blood vessels of other organs and vascular in vitro models.
Collapse
Affiliation(s)
- Ruslan Rust
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | - Tunahan Kirabali
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | - Lisa Grönnert
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Berre Dogancay
- Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | | | | | - Carsten Werner
- Leibniz Institute for Polymer Research, Dresden, Germany
| | - Bàrbara Laviña
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Luka Kulic
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | - Roger M Nitsch
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | - Christian Tackenberg
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| | - Martin E Schwab
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.,Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zürich, Zurich, Switzerland
| |
Collapse
|
13
|
Xu Y, He Q, Wang M, Wang X, Gong F, Bai L, Zhang J, Wang W. Quantifying blood-brain-barrier leakage using a combination of evans blue and high molecular weight FITC-Dextran. J Neurosci Methods 2019; 325:108349. [PMID: 31283939 DOI: 10.1016/j.jneumeth.2019.108349] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/04/2019] [Accepted: 07/04/2019] [Indexed: 02/05/2023]
Abstract
BACKGROUND Evans blue (EB) is the most widely used tracer to assess BBB leakage. However, a well-established method to obtain visualized and quantitative results of EB extravasation is presently unavailable. NEW METHOD We reported a novel method to quantify BBB leakage by combining EB and high molecular weight FITC-Dextran (2000 kDa). EB was used for a long circulation duration (60 min) to detect BBB leakage. FITC-Dextran was used for a short circulation duration (10 min) to outline vascular contours. Confocal microscope imaging was used to obtain visualized images of BBB leakage. The result of dividing integrated optical density of EB by vascular areas outlined by FITC-Dextran was treated as the quantification of BBB leakage. RESULTS This method proved workable in quantifying BBB leakage of specific regions in lipopolysaccharide-induced BBB disruption mice and apoE-/- mice. Sections processed with this method enabled further immunofluorescence staining. Through combining the results of EB extravasation and immunofluorescence staining, the colocalization of specific proteins and BBB disruption was achieved. COMPARISON WITH EXISTING METHODS Colorimetric and spectrophotometric methods provide us with quantitative results of EB extravasation but fail to locate the specific regions. Fluorescence microscopy imaging can locate specific regions of EB extravasation but a well-established quantitative method is presently unavailable. Our method combines advantages of above two classic methods, providing us with visualized and quantitative information of BBB leakage based on EB extravasation in specific cerebral regions. CONCLUSIONS The proposed method proved powerful in quantifying BBB leakage of specific regions, which may benefit studies regarding BBB disruption.
Collapse
Affiliation(s)
- Yangyang Xu
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Qi He
- Department of Neonatology, West China Second University Hospital, Sichuan University, Chengdu, 610041, China
| | - Mengqi Wang
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Xin Wang
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Feilong Gong
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Lin Bai
- Core Facility of West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jie Zhang
- Core Facility of West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Wei Wang
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, 610041, China.
| |
Collapse
|
14
|
Aleithe S, Blietz A, Mages B, Hobusch C, Härtig W, Michalski D. Transcriptional Response and Morphological Features of the Neurovascular Unit and Associated Extracellular Matrix After Experimental Stroke in Mice. Mol Neurobiol 2019; 56:7631-7650. [PMID: 31089963 PMCID: PMC6815284 DOI: 10.1007/s12035-019-1604-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 04/10/2019] [Indexed: 12/18/2022]
Abstract
Experimental stroke studies yielded insights into single reactions of the neurovascular unit (NVU) and associated extracellular matrix (ECM). However, the extent of simultaneous processes caused by ischemia and their underlying transcriptional changes are still poorly understood. Strictly following the NVU and ECM concept, this study explored transcriptional responses of cellular and non-cellular components as well as their morphological characteristics following ischemia. Mice were subjected to 4 or 24 h of unilateral middle cerebral artery occlusion. In the neocortex and the striatum, cytoskeletal and glial elements as well as blood-brain barrier and ECM components were analyzed using real-time PCR. Western blot analyses allowed characterization of protein levels and multiple immunofluorescence labeling enabled morphological assessment. Out of 37 genes analyzed, the majority exhibited decreased mRNA levels in ischemic areas, while changes occurred as early as 4 h after ischemia. Down-regulated mRNA levels were predominantly localized in the neocortex, such as the structural elements α-catenin 2, N-cadherin, β-catenin 1, and βIII-tubulin, consistently decreasing 4 and 24 h after ischemia. However, a few genes, e.g., claudin-5 and Pcam1, exhibited increased mRNA levels after ischemia. For several components such as βIII-tubulin, N-cadherin, and β-catenin 1, matching transcriptional and immunofluorescence signals were obtained, whereas a few markers including neurofilaments exhibited opposite directions. In conclusion, the variety in gene regulation emphasizes the complexity of interactions within the ischemia-affected NVU and ECM. These data might help to focus future research on a set of highly sensitive elements, which might prospectively facilitate neuroprotective strategies beyond the traditional single target perspective.
Collapse
Affiliation(s)
- Susanne Aleithe
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany.
- University of Leipzig, Liebigstr. 19, 04103, Leipzig, Germany.
| | - Alexandra Blietz
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany
- University of Leipzig, Liebigstr. 19, 04103, Leipzig, Germany
| | - Bianca Mages
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany
- Institute of Anatomy, University of Leipzig, Liebigstr. 13, 04103, Leipzig, Germany
| | - Constance Hobusch
- Institute of Anatomy, University of Leipzig, Liebigstr. 13, 04103, Leipzig, Germany
| | - Wolfgang Härtig
- University of Leipzig, Liebigstr. 19, 04103, Leipzig, Germany
| | - Dominik Michalski
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103, Leipzig, Germany.
| |
Collapse
|
15
|
Liu S, Chang L, Wei C. The sonic hedgehog pathway mediates Tongxinluo capsule‐induced protection against blood‐brain barrier disruption after ischaemic stroke in mice. Basic Clin Pharmacol Toxicol 2019; 124:660-669. [DOI: 10.1111/bcpt.13186] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 11/28/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Shen Liu
- Department of Traditional Chinese Medicine, Shandong Provincial Qianfoshan Hospital Shandong University Jinan China
- Key Laboratory of State Administration of TCM (Cardio‐Cerebral Vessel Collateral Disease) Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
- National Key Laboratory of Collateral Disease Research and Innovative Chinese Medicine Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
| | - Liping Chang
- Key Laboratory of State Administration of TCM (Cardio‐Cerebral Vessel Collateral Disease) Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
- National Key Laboratory of Collateral Disease Research and Innovative Chinese Medicine Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
| | - Cong Wei
- Key Laboratory of State Administration of TCM (Cardio‐Cerebral Vessel Collateral Disease) Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
- National Key Laboratory of Collateral Disease Research and Innovative Chinese Medicine Hebei Yiling Chinese Medicine Research Institute Shijiazhuang China
| |
Collapse
|
16
|
Schöniger S, Schütze E, Michalski D, Puchta J, Kaiser M, Härtig W. Neuropathological findings suggestive for a stroke in an alpaca (Vicugna pacos). Acta Vet Scand 2019; 61:1. [PMID: 30602394 PMCID: PMC6317207 DOI: 10.1186/s13028-018-0438-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 12/27/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This case report describes a focal brain lesion in an alpaca (Vicugna pacos). Although this is a restricted study based on a single animal, neuropathological features are reported that are most likely attributed to a vascular event with either ischemic or hemorrhagic pathology. Concerning translational issues, these findings extend neurovascular unit concept to the alpacas' brain and qualify a larger panel of stroke tissue markers for further exploration of ischemic or hemorrhagic consequences beyond the usually used small animal models in stroke research. CASE PRESENTATION A brain lesion indicative of a stroke was diagnosed in a 3-year-old female alpaca as an incidental finding during a post mortem examination. The rostral portion of the right frontal lobe contained a 1.0 × 1.5 × 1.7 cm lesion that extended immediately to the overlying leptomeninges. Microscopically, it was composed of liquefactive necrosis with cholesterol crystal deposition and associated granulomatous inflammation as well as vascularized fibrous connective tissue rimmed by proliferated astrocytes. Multiple fluorescence labeling of the affected brain regions revealed strong microgliosis as shown by immunostaining of the ionized calcium binding adapter molecule 1 and astrogliosis as demonstrated by enhanced immunoreactivity for glial fibrillary acidic protein. In parallel, a drastic neuronal loss was detected by considerably diminished immunolabeling of neuronal nuclei. Concomitantly, up-regulated immunoreactivities for collagen IV and neurofilament light chains were found in the affected tissues, indicating vascular and cytoskeletal reactions. CONCLUSIONS Driven by these neuropathological features, the incidental brain lesion found in this alpaca strongly suggests an ischemic or hemorrhagic etiology. However, since typical hallmarks became verifiable as previously described for other species affected by focal cerebral ischemia, the lesion is more likely related to an ischemic event. Nevertheless, as such cellular alterations might be difficult to distinguish from other brain lesions as for instance caused by inflammatory processes, adjuvant observations and species-related features need to be considered for etiological interpretations. Indeed, the lack of neurological deficits is likely attributed to the location of the lesion within the rostral aspect of the right frontal lobe of the alpacas' brain. Further, fibroblast migration from the meninges likely caused the intralesional scar formation.
Collapse
|
17
|
Methods to Quantify Nanomaterial Association with, and Distribution Across, the Blood-Brain Barrier In Vivo. Methods Mol Biol 2019; 1894:281-299. [PMID: 30547467 DOI: 10.1007/978-1-4939-8916-4_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The role and functional anatomy of the blood-brain barrier (BBB) is summarized to enable the investigator to appropriately address evaluation of nanomaterial interaction with, and distribution across, it into brain tissue (parenchyma). Transport mechanisms across the BBB are presented, in relation to nanomaterial physicochemical properties. Measures and test substances to assess BBB integrity/disruption/permeation are introduced, along with how they are used to interpret the results obtained with the presented methods. Experimental pitfalls and misinterpretation of results of studies of brain nanomaterial uptake are briefly summarized, that can be avoided with the methods presented in this chapter. Two methods are presented. The in situ brain perfusion technique is used to determine rate and extent of nanomaterial distribution into the brain. The capillary depletion method separates brain parenchymal tissue from the endothelial cells that contribute to the BBB. It is used to verify nanomaterial brain tissue entry. These methods are best used together, the latter refining the results obtained with the former. Details of the materials and equipment needed to conduct these methods, and description of the procedures and data interpretation, are provided.
Collapse
|
18
|
Jin X, Riew TR, Kim HL, Kim S, Lee MY. Spatiotemporal Expression of GRP78 in the Blood Vessels of Rats Treated With 3-Nitropropionic Acid Correlates With Blood-Brain Barrier Disruption. Front Cell Neurosci 2018; 12:434. [PMID: 30515081 PMCID: PMC6255854 DOI: 10.3389/fncel.2018.00434] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 11/01/2018] [Indexed: 11/13/2022] Open
Abstract
Glucose-regulated protein (GRP78) or BiP, a 78-kDa chaperone protein located in the endoplasmic reticulum (ER), has recently been reported to be involved in the neuroglial response to ischemia-induced ER stress. The present study was designed to study the expression patterns of this protein and the cell types involved in the induction of GRP78 expression in rats treated with the mitochondrial toxin 3-nitropropionic acid (3-NP). GRP78 immunoreactivity was almost exclusively localized to striatal neurons in saline-treated controls, but GRP78 expression was induced in activated glial cells, including reactive astrocytes and activated microglia/macrophages, in the striata of rats treated with 3-NP. In the lesion core, increased GRP78 immunoreactivity was observed in the vasculature; this was evident in the lesion periphery of the core at 3 days after lesion induction, and was evenly distributed throughout the lesion core by 7 days after lesion induction. Vascular GRP78 expression was correlated, both temporally and spatially, with infiltration of activated microglia into the lesion core. In addition, this was coincident with the time and pattern of blood-brain barrier (BBB) leakage, detected by the extravasation of fluorescein isothiocyanate-albumin, an established BBB permeability marker. Vascular GRP78-positive cells in the lesion core were identified as endothelial cells, smooth muscle cells, and adventitial fibroblast-like cells, in which GRP78 protein was specifically localized to the cisternae of the rough ER and perinuclear cisternae, but not to other organelles such as mitochondria or nuclei. Thus, our data provide novel insights into the phenotypic and functional heterogeneity of GRP78-positive cells within the lesion core, suggesting the involvement of GRP78 in the activation/recruitment of activated microglia/macrophages and its potential role in BBB impairment in response to a 3-NP-mediated neurotoxic insult.
Collapse
Affiliation(s)
- Xuyan Jin
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, South Korea.,Department of Biomedicine and Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Tae-Ryong Riew
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Hong Lim Kim
- Integrative Research Support Center, Laboratory of Electron Microscope, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Soojin Kim
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Mun-Yong Lee
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, South Korea.,Department of Biomedicine and Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| |
Collapse
|
19
|
Jandke S, Garz C, Schwanke D, Sendtner M, Heinze HJ, Carare RO, Schreiber S. The association between hypertensive arteriopathy and cerebral amyloid angiopathy in spontaneously hypertensive stroke-prone rats. Brain Pathol 2018; 28:844-859. [PMID: 30062722 PMCID: PMC8028507 DOI: 10.1111/bpa.12629] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We aimed to test the hypothesis that in spontaneously hypertensive stroke‐prone rats (SHRSP), non‐amyloid cerebral small vessel disease/hypertensive arteriopathy (HA) results in vessel wall injury that may promote cerebral amyloid angiopathy (CAA). Our study comprised 21 male SHRSP (age 17–44 weeks) and 10 age‐ and sex‐matched Wistar control rats, that underwent two‐photon (2PM) imaging of the arterioles in the parietal cortex using Methoxy‐X04, Dextran and cerebral blood flow (CBF) measurements. Our data suggest that HA in SHRSP progresses in a temporal and age‐dependent manner, starting from small vessel wall damage (stage 1A), proceeding to CBF reduction (stage 1B), non‐occlusive (stage 2), and finally, occlusive thrombi (stage 3). Wistar animals also demonstrated small vessel wall damage, but were free of any of the later HA stages. Nearly half of all SHRSP additionally displayed vascular Methoxy‐X04 positivity indicative of cortical CAA. Vascular β‐amyloid deposits were found in small vessels characterized by thrombotic occlusions (stage 2 or 3). Post‐mortem analysis of the rat brains confirmed the findings derived from intravital 2PM microscopy. Our data thus overall suggest that advanced HA may play a role in CAA development with the two small vessel disease entities might be related to the same pathological spectrum of the aging brain.
Collapse
Affiliation(s)
- Solveig Jandke
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE) within the Helmholtz Association, Magdeburg, Germany
| | - Cornelia Garz
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE) within the Helmholtz Association, Magdeburg, Germany
| | - Daniel Schwanke
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE) within the Helmholtz Association, Magdeburg, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University of Würzburg, Germany
| | - Hans-Jochen Heinze
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE) within the Helmholtz Association, Magdeburg, Germany
| | | | - Stefanie Schreiber
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE) within the Helmholtz Association, Magdeburg, Germany
| |
Collapse
|
20
|
Blood-Brain Barrier Leakage during Early Epileptogenesis Is Associated with Rapid Remodeling of the Neurovascular Unit. eNeuro 2018; 5:eN-NWR-0123-18. [PMID: 29854942 PMCID: PMC5975718 DOI: 10.1523/eneuro.0123-18.2018] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 04/01/2018] [Indexed: 01/26/2023] Open
Abstract
Increased permeability of the blood-brain barrier (BBB) following cerebral injury results in regional extravasation of plasma proteins and can critically contribute to the pathogenesis of epilepsy. Here, we comprehensively explore the spatiotemporal evolution of a main extravasation component, albumin, and illuminate associated responses of the neurovascular unit (NVU) contributing to early epileptogenic neuropathology. We applied translational in vivo MR imaging and complementary immunohistochemical analyses in the widely used rat pilocarpine post-status epilepticus (SE) model. The observed rapid BBB leakage affected major epileptogenesis-associated brain regions, peaked between 1 and 2 d post-SE, and rapidly declined thereafter, accompanied by cerebral edema generally following the same time course. At peak of BBB leakage, serum albumin colocalized with NVU constituents, such as vascular components, neurons, and brain immune cells. Surprisingly, astroglial markers did not colocalize with albumin, and aquaporin-4 (AQP4) was clearly reduced in areas of leaky BBB, indicating a severe disturbance of astrocyte-mediated endothelial-neuronal coupling. In addition, a distinct adaptive reorganization process of the NVU vasculature apparently takes place at sites of albumin presence, substantiated by reduced immunoreactivity of endothelial and changes in vascular basement membrane markers. Taken together, degenerative events at the level of the NVU, affecting vessels, astrocytes, and neurons, seem to outweigh reconstructive processes. Considering the rapidly occurring BBB leakage and subsequent impairment of the NVU, our data support the necessity of a prompt BBB-restoring treatment as one component of rational therapeutic intervention to prevent epileptogenesis and the development of other detrimental sequelae of SE.
Collapse
|
21
|
Michalski D, Keck AL, Grosche J, Martens H, Härtig W. Immunosignals of Oligodendrocyte Markers and Myelin-Associated Proteins Are Critically Affected after Experimental Stroke in Wild-Type and Alzheimer Modeling Mice of Different Ages. Front Cell Neurosci 2018; 12:23. [PMID: 29467621 PMCID: PMC5807905 DOI: 10.3389/fncel.2018.00023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/15/2018] [Indexed: 12/31/2022] Open
Abstract
Because stroke therapies are still limited and patients are often concerned by long-term sequelae with significant impairment of daily living, elaborated neuroprotective strategies are needed. During the last decades, research substantially improved the knowledge on cellular pathologies responsible for stroke-related tissue damage. In this context, the neurovascular unit (NVU) concept has been established, summarizing the affections of neurons, associated astrocytes and the vasculature. Although oligodendrocytes were already identified to play a major role in other brain pathologies, their role during stroke evolution and long-lasting tissue damage is poorly understood. This study aims to explore oligodendrocyte structures, i.e., oligodendrocytes and their myelin-associated proteins, after experimental focal cerebral ischemia. For translational issues, different ages and genotypes including an Alzheimer-like background were considered to mimic potential co-morbidities. Three- and 12-month-old wild-type and triple-transgenic mice were subjected to unilateral middle cerebral artery occlusion. Immunofluorescence labeling was performed on forebrain tissues affected by 24 h of ischemia to visualize the oligodendrocyte-specific protein (OSP), the myelin basic protein (MBP), and the neuron-glia antigen 2 (NG2) with reference to the ischemic lesion. Subsequent analyses concomitantly detected the vasculature and the 2′, 3′-cyclic nucleotide-3′-phosphodiesterase (CNPase) to consider the NVU concept and to explore the functional relevance of histochemical data on applied oligodendrocyte markers. While the immunosignal of NG2 was found to be nearly absent 24 h after ischemia onset, enhanced immunoreactivities for OSP and especially MBP were observed in close regional association to the vasculature. Added quantitative analyses based on inter-hemispheric differences of MBP-immunoreactivity revealed a shell-like pattern with a significant increase directly in the ischemic core, followed by a gradual decline toward the striatum, the ischemic border zone and the lateral neocortex. This observation was consistent in subsequent analyses on the potential impact of age and genetic background. Furthermore, immunoreactivities for CNPase, MBP, and OSP were found to be simultaneously enhanced. In conclusion, this study provides evidence for a critical role of oligodendrocyte structures in the early phase after experimental stroke, strengthening their involvement in the ischemia-affected NVU. Consequently, oligodendrocytes and their myelin-associated proteins may qualify as potential targets for neuroprotective and regenerative approaches in stroke.
Collapse
Affiliation(s)
| | - Anna L Keck
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | | | | | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| |
Collapse
|
22
|
Hypercholesterolemia induced cerebral small vessel disease. PLoS One 2017; 12:e0182822. [PMID: 28796818 PMCID: PMC5552130 DOI: 10.1371/journal.pone.0182822] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 07/25/2017] [Indexed: 01/01/2023] Open
Abstract
Background While hypercholesterolemia plays a causative role for the development of ischemic stroke in large vessels, its significance for cerebral small vessel disease (CSVD) remains unclear. We thus aimed to understand the detailed relationship between hypercholesterolemia and CSVD using the well described Ldlr-/- mouse model. Methods We used Ldlr-/- mice (n = 16) and wild-type (WT) mice (n = 15) at the age of 6 and 12 months. Ldlr-/- mice develop high plasma cholesterol levels following a high fat diet. We analyzed cerebral capillaries and arterioles for intravascular erythrocyte accumulations, thrombotic vessel occlusions, blood-brain barrier (BBB) dysfunction and microbleeds. Results We found a significant increase in the number of erythrocyte stases in 6 months old Ldlr-/- mice compared to all other groups (P < 0.05). Ldlr-/- animals aged 12 months showed the highest number of thrombotic occlusions while in WT animals hardly any occlusions could be observed (P < 0.001). Compared to WT mice, Ldlr-/- mice did not display significant gray matter BBB breakdown. Microhemorrhages were observed in one Ldlr-/- mouse that was 6 months old. Results did not differ when considering subcortical and cortical regions. Conclusions In Ldlr-/- mice, hypercholesterolemia is related to a thrombotic CSVD phenotype, which is different from hypertension-related CSVD that associates with a hemorrhagic CSVD phenotype. Our data demonstrate a relationship between hypercholesterolemia and the development of CSVD. Ldlr-/- mice appear to be an adequate animal model for research into CSVD.
Collapse
|
23
|
Breuer H, Meier M, Schneefeld S, Härtig W, Wittneben A, Märkel M, Ross TL, Bengel FM, Bankstahl M, Bankstahl JP. Multimodality imaging of blood-brain barrier impairment during epileptogenesis. J Cereb Blood Flow Metab 2017; 37:2049-2061. [PMID: 27435624 PMCID: PMC5464700 DOI: 10.1177/0271678x16659672] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Insult-associated blood-brain barrier leakage is strongly suggested to be a key step during epileptogenesis. In this study, we used three non-invasive translational imaging modalities, i.e. positron emission tomography, single photon emission computed tomography, and magnetic resonance imaging, to evaluate BBB leakage after an epileptogenic brain insult. Sprague-Dawley rats were scanned during early epileptogenesis initiated by status epilepticus. Positron emission tomography and single photon emission computed tomography scans were performed using the novel tracer [68Ga]DTPA or [99mTc]DTPA, respectively. Magnetic resonance imaging included T2 and post-contrast T1 sequence after infusion of Gd-DTPA, gadobutrol, or Gd-albumin. All modalities revealed increased blood-brain barrier permeability 48 h post status epilepticus, mainly in epileptogenesis-associated brain regions like hippocampus, piriform cortex, thalamus, or amygdala. In hippocampus, Gd-DTPA-enhanced T1 magnetic resonance imaging signal was increased by 199%, [68Ga]DTPA positron emission tomography by 37%, and [99mTc]DTPA single photon emission computed tomography by 56%. Imaging results were substantiated by histological detection of albumin extravasation. Comparison with quantitative positron emission tomography and single photon emission computed tomography shows that magnetic resonance imaging sequences successfully amplify the signal from a moderate amount of extravasated DTPA molecules, enabling sensitive detection of blood-brain barrier disturbance in epileptogenesis. Imaging of the disturbed blood-brain barrier will give further pathophysiologic insights, will help to stratify anti-epileptogenic treatment targeting blood-brain barrier integrity, and may serve as a prognostic biomarker.
Collapse
Affiliation(s)
- Heike Breuer
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany.,2 Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover and Center for Systems Neuroscience, Hannover, Germany
| | - Martin Meier
- 3 Preclinical Imaging Labs, Central Laboratory Animal Facility & Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | - Sophie Schneefeld
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Wolfgang Härtig
- 4 Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Alexander Wittneben
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Martin Märkel
- 4 Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Tobias L Ross
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Frank M Bengel
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| | - Marion Bankstahl
- 2 Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover and Center for Systems Neuroscience, Hannover, Germany
| | - Jens P Bankstahl
- 1 Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany
| |
Collapse
|
24
|
Up-regulation of neurofilament light chains is associated with diminished immunoreactivities for MAP2 and tau after ischemic stroke in rodents and in a human case. J Chem Neuroanat 2016; 78:140-148. [DOI: 10.1016/j.jchemneu.2016.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 09/09/2016] [Accepted: 09/09/2016] [Indexed: 11/18/2022]
|
25
|
Multiple beneficial effects of melanocortin MC 4 receptor agonists in experimental neurodegenerative disorders: Therapeutic perspectives. Prog Neurobiol 2016; 148:40-56. [PMID: 27916623 DOI: 10.1016/j.pneurobio.2016.11.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 11/22/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022]
Abstract
Melanocortin peptides induce neuroprotection in acute and chronic experimental neurodegenerative conditions. Melanocortins likewise counteract systemic responses to brain injuries. Furthermore, they promote neurogenesis by activating critical signaling pathways. Melanocortin-induced long-lasting improvement in synaptic activity and neurological performance, including learning and memory, sensory-motor orientation and coordinated limb use, has been consistently observed in experimental models of acute and chronic neurodegeneration. Evidence indicates that the neuroprotective and neurogenic effects of melanocortins, as well as the protection against systemic responses to a brain injury, are mediated by brain melanocortin 4 (MC4) receptors, through an involvement of the vagus nerve. Here we discuss the targets and mechanisms underlying the multiple beneficial effects recently observed in animal models of neurodegeneration. We comment on the potential clinical usefulness of melanocortin MC4 receptor agonists as neuroprotective and neuroregenerative agents in ischemic stroke, subarachnoid hemorrhage, traumatic brain injury, spinal cord injury, and Alzheimer's disease.
Collapse
|
26
|
A novel approach for mechanical tissue characterization indicates decreased elastic strength in brain areas affected by experimental thromboembolic stroke. Neuroreport 2016; 26:583-7. [PMID: 26053700 PMCID: PMC4461357 DOI: 10.1097/wnr.0000000000000395] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
As treatment of ischemic stroke remains a challenge with respect to the failure of numerous neuroprotective attempts, there is an ongoing need for better understanding of pathophysiological mechanisms causing tissue damage. Although ischemic outcomes have been studied extensively at the cellular and molecular level using histological and biochemical methods, properties of ischemia-affected brain tissue with respect to mechanical integrity have not been addressed so far. As a novel approach, this study used fluorescence-based detection of regions affected by experimental thromboembolic stroke in combination with scanning force microscopy to examine mechanical alterations in selected rat brain areas. Twenty-five hours after onset of ischemia, a decreased elastic strength in the striatum as the region primarily affected by ischemia was found compared with the contralateral nonaffected hemisphere. Additional intrahemispheric analyses showed decreased elastic strength in the ischemic border zone compared with the more severely affected striatum. In conclusion, these data strongly indicate a critical alteration in mechanical tissue integrity caused by focal cerebral ischemia. Further, on the basis of data that have been obtained in relation to the ischemic border zone, a shell-like pattern of mechanical tissue damage was found in good accordance with the penumbra concept. These findings might enable the development of specific therapeutic interventions to protect affected areas from critical loss of mechanical integrity.
Collapse
|
27
|
Wu C, Chen J, Chen C, Wang W, Wen L, Gao K, Chen X, Xiong S, Zhao H, Li S. Wnt/β-catenin coupled with HIF-1α/VEGF signaling pathways involved in galangin neurovascular unit protection from focal cerebral ischemia. Sci Rep 2015; 5:16151. [PMID: 26537366 PMCID: PMC4633613 DOI: 10.1038/srep16151] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 06/17/2015] [Indexed: 01/07/2023] Open
Abstract
Microenvironmental regulation has become a promising strategy for complex disease treatment. The neurovascular unit (NVU), as the key structural basis to maintain an optimal brain microenvironment, has emerged as a new paradigm to understand the pathology of stroke. In this study, we investigated the effects of galangin, a natural flavonoid isolated from the rhizome of Alpina officinarum Hance, on NVU microenvironment improvement and associated signal pathways in rats impaired by middle cerebral artery occlusion (MCAO). Galangin ameliorated neurological scores, cerebral infarct volume and cerebral edema and reduced the concentration of Evans blue (EB) in brain tissue. NVU ultrastructural changes were also improved by galangin. RT-PCR and western blot revealed that galangin protected NVUs through the Wnt/β-catenin pathway coupled with HIF-1α and vascular endothelial growth factor (VEGF). VEGF and β-catenin could be the key nodes of these two coupled pathways. In conclusion, Galangin might function as an anti-ischemic stroke drug by improving the microenvironment of NVUs.
Collapse
Affiliation(s)
- Chuanhong Wu
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China.,State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, 999078, China
| | - Jianxin Chen
- Beijing University of Chinese Medicine, Beijing 100029, China
| | - Chang Chen
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Wei Wang
- Beijing University of Chinese Medicine, Beijing 100029, China
| | - Limei Wen
- The first Affiliated Hospital of Xinjiang Medical University, Xinjiang, 830054, China
| | - Kuo Gao
- Beijing University of Chinese Medicine, Beijing 100029, China
| | - Xiuping Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, 999078, China
| | - Sihuai Xiong
- Beijing No.166 High School, Beijing 100006, China
| | - Huihui Zhao
- Beijing University of Chinese Medicine, Beijing 100029, China
| | - Shaojing Li
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China.,Beijing University of Chinese Medicine, Beijing 100029, China
| |
Collapse
|
28
|
Sakadžić S, Lee J, Boas DA, Ayata C. High-resolution in vivo optical imaging of stroke injury and repair. Brain Res 2015; 1623:174-92. [PMID: 25960347 PMCID: PMC4569527 DOI: 10.1016/j.brainres.2015.04.044] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 04/21/2015] [Accepted: 04/22/2015] [Indexed: 12/15/2022]
Abstract
Central nervous system (CNS) function and dysfunction are best understood within a framework of interactions between neuronal, glial and vascular compartments comprising the neurovascular unit (NVU), all of which contribute to stroke-induced CNS injury, plasticity, repair, and recovery. Recent advances in in vivo optical microscopy have enabled us to observe and interrogate cells and their processes with high spatial resolution in real time and in their natural environment deep in the brain tissue. Here, we review some of these state-of-the-art imaging techniques with an emphasis on imaging the interactions among the constituents of the NVU during ischemic injury and repair in small animal models. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
Collapse
Affiliation(s)
- Sava Sakadžić
- Optics Division, MHG/MIT/HMS Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA.
| | - Jonghwan Lee
- Optics Division, MHG/MIT/HMS Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - David A Boas
- Optics Division, MHG/MIT/HMS Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Cenk Ayata
- Neurovascular Research Laboratory, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA; Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| |
Collapse
|
29
|
Blood-brain barrier breakdown involves four distinct stages of vascular damage in various models of experimental focal cerebral ischemia. J Cereb Blood Flow Metab 2015; 35:292-303. [PMID: 25425076 PMCID: PMC4426746 DOI: 10.1038/jcbfm.2014.199] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 10/16/2014] [Accepted: 10/17/2014] [Indexed: 12/18/2022]
Abstract
Ischemic stroke not only impairs neuronal function but also affects the cerebral vasculature as indicated by loss of blood-brain barrier (BBB) integrity. Therefore, therapeutical recanalization includes an enhanced risk for hemorrhagic transformation and bleeding, traditionally attributed to a 'reperfusion injury'. To investigate the mechanisms underlying ischemia-/reperfusion-related BBB opening, we applied multiple immunofluorescence labeling and electron microscopy in a rat model of thromboembolic stroke as well as mouse models of permanent and transient focal cerebral ischemia. In these models, areas exhibiting BBB breakdown were identified by extravasation of intravenously administered fluorescein isothiocyanate (FITC)-albumin. After 24 hours, expression of markers for tight and adherens junctions in areas of FITC-albumin leakage consistently remained unaltered in the applied models. However, lectin staining with isolectin B4 indicated structural alterations in the endothelium, which were confirmed by electron microscopy. While ultrastructural alterations in endothelial cells did not differ between the applied models including the reperfusion scenario, we regularly identified vascular alterations, which we propose to reflect four distinct stages of BBB breakdown with ultimate loss of endothelial cells. Therefore, our data strongly suggest that ischemia-related BBB failure is predominantly caused by endothelial degeneration. Thus, protecting endothelial cells may represent a promising therapeutical approach in addition to the established recanalizing strategies.
Collapse
|
30
|
Liu DF, Qian C, An YL, Chang D, Ju SH, Teng GJ. Magnetic resonance imaging of post-ischemic blood-brain barrier damage with PEGylated iron oxide nanoparticles. NANOSCALE 2014; 6:15161-7. [PMID: 25374303 DOI: 10.1039/c4nr03942d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Blood-brain barrier (BBB) damage during ischemia may induce devastating consequences like cerebral edema and hemorrhagic transformation. This study presents a novel strategy for dynamically imaging of BBB damage with PEGylated supermagnetic iron oxide nanoparticles (SPIONs) as contrast agents. The employment of SPIONs as contrast agents made it possible to dynamically image the BBB permeability alterations and ischemic lesions simultaneously with T2-weighted MRI, and the monitoring could last up to 24 h with a single administration of PEGylated SPIONs in vivo. The ability of the PEGylated SPIONs to highlight BBB damage by MRI was demonstrated by the colocalization of PEGylated SPIONs with Gd-DTPA after intravenous injection of SPION-PEG/Gd-DTPA into a mouse. The immunohistochemical staining also confirmed the leakage of SPION-PEG from cerebral vessels into parenchyma. This study provides a novel and convenient route for imaging BBB alteration in the experimental ischemic stroke model.
Collapse
Affiliation(s)
- Dong-Fang Liu
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Medical School, Zhongda Hospital, Southeast University, No. 87, Dingjiaqiao, Nanjing 210009, China.
| | | | | | | | | | | |
Collapse
|
31
|
Lehmann J, Härtig W, Seidel A, Füldner C, Hobohm C, Grosche J, Krueger M, Michalski D. Inflammatory cell recruitment after experimental thromboembolic stroke in rats. Neuroscience 2014; 279:139-54. [DOI: 10.1016/j.neuroscience.2014.08.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 07/28/2014] [Accepted: 08/17/2014] [Indexed: 10/24/2022]
|
32
|
Ceccariglia S, D’altocolle A, Del Fa’ A, Silvestrini A, Barba M, Pizzolante F, Repele A, Michetti F, Gangitano C. Increased expression of Aquaporin 4 in the rat hippocampus and cortex during trimethyltin-induced neurodegeneration. Neuroscience 2014; 274:273-88. [DOI: 10.1016/j.neuroscience.2014.05.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/21/2014] [Accepted: 05/21/2014] [Indexed: 12/12/2022]
|
33
|
Niklass S, Stoyanov S, Garz C, Bueche CZ, Mencl S, Reymann K, Heinze HJ, Carare RO, Kleinschnitz C, Schreiber S. Intravital imaging in spontaneously hypertensive stroke-prone rats-a pilot study. EXPERIMENTAL & TRANSLATIONAL STROKE MEDICINE 2014; 6:1. [PMID: 24461046 PMCID: PMC3996193 DOI: 10.1186/2040-7378-6-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/19/2014] [Indexed: 12/02/2022]
Abstract
Background There is growing evidence that endothelial failure and subsequent blood brain barrier (BBB) breakdown initiate cerebral small vessel disease (CSVD) pathology. In spontaneously hypertensive stroke-prone rats (SHRSP) endothelial damage is indicated by intraluminal accumulations of erythrocytes (erythrocyte thrombi) that are not observed with current magnetic resonance imaging techniques. Two-photon microscopy (2 PM) offers the potential for real-time direct detection of the small vasculature. Thus, within this pilot study we investigated the sensitivity of 2 PM to detect erythrocyte thrombi expressing initiating CSVD phenomena in vivo. Methods Eight SHRSP and 13 Wistar controls were used for in vivo imaging and subsequent histology with haematoxylin-eosin (HE). For 2 PM, cerebral blood vessels were labeled by fluorescent Dextran (70 kDa) applied intraorbitally. The correlation between vascular erythrocyte thrombi observed by 2 PM and HE-staining was assessed. Artificial surgical damage and parenchymal Dextran distribution were analyzed postmortem. Results Dextran was distributed within the small vessel walls and co-localized with IgG. Artificial surgical damage was comparable between SHRSP and Wistar controls and mainly affected the small vasculature. In fewer than 20% of animals there was correlation between erythrocyte thrombi as observed with 2 PM and histologically with HE. Conclusions Contrary to our initial expectations, there was little agreement between intravital 2 PM imaging and histology for the detection of erythrocyte thrombi. Two-photon microscopy is a valuable technique that complements but does not replace the value of conventional histology.
Collapse
Affiliation(s)
- Solveig Niklass
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, 39120 Magdeburg, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Bueche CZ, Hawkes C, Garz C, Vielhaber S, Attems J, Knight RT, Reymann K, Heinze HJ, Carare RO, Schreiber S. Hypertension drives parenchymal β-amyloid accumulation in the brain parenchyma. Ann Clin Transl Neurol 2014; 1:124-9. [PMID: 25356391 PMCID: PMC4212487 DOI: 10.1002/acn3.27] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 11/15/2013] [Accepted: 12/05/2013] [Indexed: 01/27/2023] Open
Abstract
There is substantial controversy regarding the causative role of amyloid β (Aβ) deposition in Alzheimer's disease (AD). The cerebrovasculature plays an important role in the elimination of Aβ from the brain and hypertension is a well-known risk factor for AD. In spontaneously hypertensive stroke-prone rats (SHRSP), an animal model of chronic arterial hypertension, cerebral small vessel disease (CSVD) leads to age-dependent parenchymal Aβ accumulation similar to that observed in AD. These data approve the neuropathological link between CSVD and AD, confirm the challenge that parenchymal Aβ deposition is a specific marker for AD and disclose the meaning of SHRSP as valid experimental model to investigate the association between hypertension, CSVD, and Aβ plaques.
Collapse
Affiliation(s)
- Celine Z Bueche
- Department of Neurology, Otto-von-Guericke University Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Cheryl Hawkes
- Faculty of Medicine, University of Southampton Southampton, United Kingdom
| | - Cornelia Garz
- Department of Neurology, Otto-von-Guericke University Magdeburg, Germany
| | - Stefan Vielhaber
- Department of Neurology, Otto-von-Guericke University Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Johannes Attems
- Institute for Aging and Health, Newcastle University Newcastle, United Kingdom
| | - Robert T Knight
- Helen Wills Neuroscience Institute and Department of Psychology, University of California Berkeley, California
| | - Klaus Reymann
- German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Neurology, Otto-von-Guericke University Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Roxana O Carare
- Faculty of Medicine, University of Southampton Southampton, United Kingdom
| | - Stefanie Schreiber
- Department of Neurology, Otto-von-Guericke University Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| |
Collapse
|
35
|
Protein markers of cerebrovascular disruption of neurovascular unit: immunohistochemical and imaging approaches. Rev Neurosci 2014; 25:481-507. [DOI: 10.1515/revneuro-2013-0041] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 03/22/2014] [Indexed: 12/15/2022]
|
36
|
Pelz J, Härtig W, Weise C, Hobohm C, Schneider D, Krueger M, Kacza J, Michalski D. Endothelial barrier antigen-immunoreactivity is conversely associated with blood-brain barrier dysfunction after embolic stroke in rats. Eur J Histochem 2013; 57:e38. [PMID: 24441191 PMCID: PMC3896040 DOI: 10.4081/ejh.2013.e38] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Revised: 11/21/2013] [Accepted: 10/18/2013] [Indexed: 12/12/2022] Open
Abstract
While the concept of the Neurovascular Unit (NVU) is increasingly recognized for exploring mechanisms of tissue damage in ischemic stroke, immunohistochemical analyses are of interest to specifically visualize constituents like the endothelium. Changes in immunoreactivity have also been discussed to reflect functional aspects, e.g., the integrity of the blood-brain barrier (BBB). This study aimed to characterize the endothelial barrier antigen (EBA) as addressed by the antibody SMI-71 in a rat model of embolic stroke, considering FITC-albumin as BBB leakage marker and serum levels of BBB-associated matrix metalloproteinases (MMPs) to explore its functional significance. Five and 25 h after ischemia onset, regions with decreased BBB integrity exhibited a reduction in number and area of EBA-immunopositive vessels, while the stained area per vessel was not affected. Surprisingly, EBA content of remaining vessels tended to be increased in areas of BBB dysfunction. Analyses addressing this interrelation resulted in a significant and inverse correlation between the vessels' EBA content and degree of BBB permeability. In conclusion, these data provide evidence for a functional relationship between EBA-immunoreactivity and BBB dysfunction in experimental ischemic stroke. Further studies are required to explore the underlying mechanisms of altered EBA-immunoreactivity, which might help to identify novel neuroprotective strategies.
Collapse
|
37
|
Protective effect of serofendic acid, administered intravenously, on cerebral ischemia-reperfusion injury in rats. Brain Res 2013; 1532:99-105. [DOI: 10.1016/j.brainres.2013.08.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 07/26/2013] [Accepted: 08/05/2013] [Indexed: 01/09/2023]
|
38
|
A murine model of mild traumatic brain injury exhibiting cognitive and motor deficits. J Surg Res 2013; 184:981-8. [PMID: 23622728 DOI: 10.1016/j.jss.2013.03.075] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 03/14/2013] [Accepted: 03/21/2013] [Indexed: 11/22/2022]
Abstract
BACKGROUND Mild traumatic brain injury (TBI) is a serious public health concern affecting more than 1.7 million people in the United States annually. Mild TBI is difficult to diagnose and is clinically associated with impaired motor coordination and cognition. METHODS We subjected mice to a mild TBI (mTBI-1 or mTBI-2) induced by a weight drop model. We assessed brain injury histologically and biochemically, the latter by serum neuron-specific enolase and glial fibrillary acidic protein. Systemic and brain inflammation were measured by cytokine array. We determined blood-brain barrier integrity by cerebral vascular leakage of micromolecular and macromolecular fluorescent molecules. We evaluated mice using a rotarod device and novel object recognition to measure motor coordination and cognition, respectively. RESULTS Mice undergoing mTBI-1 or mTBI-2 had significant deficits in motor coordination and cognition for several days after injury compared with controls. Furthermore, both mTBI-1 and mTBI-2 caused micromolecular leakage in the blood-brain barrier, whereas only mTBI-2 caused macromolecular leakage. Serum neuron-specific enolase and glial fibrillary acidic protein were elevated acutely and corresponded to the degree of injury, but returned to baseline within 24 h. Serum cytokines interleukin-6 and keratinocyte-derived chemokine were significantly increased within 90 min of TBI. Interleukin-6 levels correlated with the degree of injury. CONCLUSIONS The current study provides a reproducible model of mild TBI in mice that exhibits pathologic features of mild TBI in humans. Furthermore, our data suggest that serum cytokines, such as IL-6, may be effective biomarkers for severity of head injury.
Collapse
|
39
|
Bueche CZ, Garz C, Kropf S, Bittner D, Li W, Goertler M, Heinze HJ, Reymann K, Braun H, Schreiber S. NAC changes the course of cerebral small vessel disease in SHRSP and reveals new insights for the meaning of stases - a randomized controlled study. EXPERIMENTAL & TRANSLATIONAL STROKE MEDICINE 2013; 5:5. [PMID: 23587288 PMCID: PMC3661381 DOI: 10.1186/2040-7378-5-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 04/10/2013] [Indexed: 11/24/2022]
Abstract
Background N-Acetylcystein (NAC) reduces the reperfusion injury and infarct size in experimental macroangiopathic stroke. Here we now investigate the impact of NAC on the development of the histopathology of microangiopathic cerebrovascular disease including initial intravasal erythrocyte accumulations, blood–brain-barrier (BBB)-disturbances, microbleeds and infarcts. Methods Spontaneously Hypertensive Stroke-Prone Rats (SHRSP) were treated with NAC (12 mg/kg body weight, daily oral application for three to 30 weeks) and compared to untreated SHRSP. In all rats the number of microbleeds, thromboses, infarcts and stases were quantified by HE-staining. Exemplary brains were stained against von Willebrand factor (vWF), IgG, Glutathione and GFAP. Results NAC animals exhibited significant more microbleeds, a greater number of vessels with BBB-disturbances, but also an elevation of Glutathione-levels in astrocytes surrounding small vessels. NAC-treatment reduced the numbers of thromboses, infarcts and arteriolar stases. Conclusions NAC reduces the frequency of thromboses and infarcts to the expense of an increase of small microbleeds in a rat model of microangiopathic cerebrovascular disease. We suppose that NAC acts via an at least partial inactivation of vWF resulting in an insufficient sealing of initial endothelial injury leading to more small microbleeds. By elevating Glutathione-levels NAC most likely exerts a radical scavenger function and protects small vessels against extended ruptures and subsequent infarcts. Finally, it reveals that stases are mainly caused by endothelial injuries and restricted thromboses.
Collapse
Affiliation(s)
- Celine Zoe Bueche
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany
| | - Cornelia Garz
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany
| | - Siegfried Kropf
- Institute of Biometry and Medical Informatics, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany
| | - Daniel Bittner
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany ; German Center for Neurodegenerative Diseases (DZNE), Brenneckestrasse 6, Magdeburg, 39118, Germany
| | - Wenjie Li
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany
| | - Michael Goertler
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany
| | - Hans-Jochen Heinze
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany ; Leibniz Institute for Neurobiology, Brenneckestrasse 6, Magdeburg, 39118, Germany ; German Center for Neurodegenerative Diseases (DZNE), Brenneckestrasse 6, Magdeburg, 39118, Germany
| | - Klaus Reymann
- Leibniz Institute for Neurobiology, Brenneckestrasse 6, Magdeburg, 39118, Germany ; German Center for Neurodegenerative Diseases (DZNE), Brenneckestrasse 6, Magdeburg, 39118, Germany
| | - Holger Braun
- German Center for Neurodegenerative Diseases (DZNE), Brenneckestrasse 6, Magdeburg, 39118, Germany
| | - Stefanie Schreiber
- Department of Neurology, Otto-von-Guericke-University, Leipziger Strasse 44, Magdeburg, 39120, Germany ; German Center for Neurodegenerative Diseases (DZNE), Brenneckestrasse 6, Magdeburg, 39118, Germany
| |
Collapse
|
40
|
Krueger M, Härtig W, Reichenbach A, Bechmann I, Michalski D. Blood-brain barrier breakdown after embolic stroke in rats occurs without ultrastructural evidence for disrupting tight junctions. PLoS One 2013; 8:e56419. [PMID: 23468865 PMCID: PMC3582567 DOI: 10.1371/journal.pone.0056419] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 01/09/2013] [Indexed: 12/27/2022] Open
Abstract
The term blood-brain barrier (BBB) relates to the ability of cerebral vessels to hold back hydrophilic and large molecules from entering the brain, thereby crucially contributing to brain homeostasis. In fact, experimental opening of endothelial tight junctions causes a breakdown of the BBB evidenced as for instance by albumin leakage. This and similar observations led to the conclusion that BBB breakdown is predominantly mediated by damage to tight junction complexes, but evidentiary ultrastructural data are rare. Since functional deficits of the BBB contribute to an increased risk of hemorrhagic transformation and brain edema after stroke, which both critically impact on the clinical outcome, we studied the mechanism of BBB breakdown using an embolic model of focal cerebral ischemia in Wistar rats to closely mimic the essential human pathophysiology. Ischemia-induced BBB breakdown was detected using intravenous injection of FITC-albumin and tight junctions in areas of FITC-albumin extravasation were subsequently studied using fluorescence and electron microscopy. Against our expectation, 25 hours after ischemia induction the morphology of tight junction complexes (identified ultrastructurally and using antibodies against the transcellular proteins occludin and claudin-5) appeared to be regularly maintained in regions where FITC-albumin massively leaked into the neuropil. Furthermore, occludin signals along pan-laminin-labeled vessels in the affected hemisphere equaled the non-affected contralateral side (ratio: 0.966 vs. 0.963; P = 0.500). Additional ultrastructural analyses at 5 and 25 h after ischemia induction clearly indicated FITC-albumin extravasation around vessels with intact tight junctions, while the endothelium exhibited enhanced transendothelial vesicle trafficking and signs of degeneration. Thus, BBB breakdown and leakage of FITC-albumin cannot be correlated with staining patterns for common tight junction proteins alone. Understanding the mechanisms causing functional endothelial alterations and endothelial damage is likely to provide novel protective targets in stroke.
Collapse
Affiliation(s)
- Martin Krueger
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
- * E-mail: (MK); (DM)
| | - Wolfgang Härtig
- Paul Flechsig Institute of Brain Research, University of Leipzig, Leipzig, Germany
| | - Andreas Reichenbach
- Paul Flechsig Institute of Brain Research, University of Leipzig, Leipzig, Germany
| | - Ingo Bechmann
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Dominik Michalski
- Department of Neurology, University of Leipzig, Leipzig, Germany
- * E-mail: (MK); (DM)
| |
Collapse
|
41
|
Jin X, Liu J, Yang Y, Liu KJ, Yang Y, Liu W. Spatiotemporal evolution of blood brain barrier damage and tissue infarction within the first 3h after ischemia onset. Neurobiol Dis 2012; 48:309-16. [DOI: 10.1016/j.nbd.2012.07.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 06/29/2012] [Accepted: 07/09/2012] [Indexed: 10/28/2022] Open
|
42
|
Braun H, Bueche CZ, Garz C, Oldag A, Heinze HJ, Goertler M, Reymann KG, Schreiber S. Stases are associated with blood-brain barrier damage and a restricted activation of coagulation in SHRSP. J Neurol Sci 2012; 322:71-6. [PMID: 22831765 DOI: 10.1016/j.jns.2012.06.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 06/04/2012] [Accepted: 06/25/2012] [Indexed: 10/28/2022]
Abstract
Cerebral small vessel disease (CSVD) is a chronically proceeding pathology of small brain vessels associated with white matter lesions, lacunar infarcts, brain atrophy and microbleeds. CSVD leads to slowly increasing cognitive and functional deficits but may also cause stroke-like symptoms, if vessels in critical brain areas are affected. Spontaneously hypertensive stroke-prone rats (SHRSP) exhibit several vascular risk factors, develop infarcts and hemorrhages and therefore represent a relevant model for the study of CSVD. Using this animal model, we recently demonstrated that intravasal accumulations of erythrocytes, we interpreted as stases, stand at the beginning of a pathological vascular cascade. After stases microbleeds occur, which are followed by reactive microthromboses. Bleeds and thromboses finally cause hemorrhagic infarcts. Immunohistochemical stainings show, that plasma proteins like IgG are deposited in the walls of vessels affected by stases. Further, we found small clots and thread-shaped aggregations of thrombocytes as well as thread-shaped structures of von Willebrand-Factor within stases. Thus, we conclude that blood-brain barrier damages occur in the neighborhood of stases and stases seem to be associated with a restricted activation of blood coagulation without formation of obstructive thromboses. Finally, we demonstrate that small vessel damage rarely appears in the cerebellum. Even animals with multiple cerebral infarcts may be free of any cerebellar vascular pathology.
Collapse
Affiliation(s)
- Holger Braun
- Deutsches Zentrum für Neurodegenerative Erkrankungen-DZNE Magdeburg, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Michalski D, Weise C, Hobohm C, Küppers-Tiedt L, Pelz J, Schneider D, Kacza J, Härtig W. Autonomic reactions and peri-interventional alterations in body weight as potential supplementary outcome parameters for thromboembolic stroke in rats. EXPERIMENTAL & TRANSLATIONAL STROKE MEDICINE 2012; 4:7. [PMID: 22510241 PMCID: PMC3398859 DOI: 10.1186/2040-7378-4-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 04/17/2012] [Indexed: 12/02/2022]
Abstract
Background Since several neuroprotectives failed to reproduce promising preclinical results under clinical conditions, efforts emerged to implement clinically relevant endpoints in animal stroke studies. Thereby, insufficient attention was given on autonomic reactions due to experimental stroke, although clinical trials reported on high functional and prognostic impact. This study focused on autonomic consequences and body weight changes in a translational relevant stroke model and investigated interrelations to different outcome measurements. Methods Forty-eight rats underwent thromboembolic middle cerebral artery occlusion (MCAO) while recording heart rate (HR) and mean arterial pressure (MAP). After assessing early functional impairment (Menzies score), animals were assigned to control procedure or potentially neuroprotective treatment with normobaric (NBO) or hyperbaric oxygen (HBO). Four or 24 hours after ischemia onset, functional impairment was re-assessed and FITC-albumin administered intravenously obtaining leakage-related blood–brain barrier (BBB) impairment. Body weight was documented prior to MCAO and 4 or 24 hours after ischemia onset. Results During MCAO, HR was found to increase significantly while MAP decreased. The amount of changes in HR was positively correlated with early functional impairment (P = 0.001): Severely affected animals provided an increase of 15.2 compared to 0.8 beats/minute in rats with low impairment (P = 0.048). Regarding body weight, a decrease of 9.4% within 24 hours after MCAO occurred, but treatment-specific alterations showed no significant correlations with respective functional or BBB impairment. Conclusions Future studies should routinely include autonomic parameters to allow inter-group comparisons and better understanding of autonomic reactions due to experimental stroke. Prospectively, autonomic consequences might represent a useful outcome parameter enhancing the methodological spectrum of preclinical stroke studies.
Collapse
Affiliation(s)
- Dominik Michalski
- Department of Neurology, University of Leipzig, Liebigstr, 20, 04103, Leipzig, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Different vascular permeability between the sensory and secretory circumventricular organs of adult mouse brain. Cell Tissue Res 2012; 349:589-603. [PMID: 22584508 DOI: 10.1007/s00441-012-1421-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 03/19/2012] [Indexed: 01/05/2023]
Abstract
The blood-brain barrier (BBB) prevents free access of circulating molecules to the brain and maintains a specialized brain environment to protect the brain from blood-derived bioactive and toxic molecules; however, the circumventricular organs (CVOs) have fenestrated vasculature. The fenestrated vasculature in the sensory CVOs, including the organum vasculosum of lamina terminalis (OVLT), subfornical organ (SFO) and area postrema (AP), allows neurons and astrocytes to sense a variety of plasma molecules and convey their information into other brain regions and the vasculature in the secretory CVOs, including median eminence (ME) and neurohypophysis (NH), permits neuronal terminals to secrete many peptides into the blood stream. The present study showed that vascular permeability of low-molecular-mass tracers such as fluorescein isothiocyanate (FITC) and Evans Blue was higher in the secretory CVOs and kidney as compared with that in the sensory CVOs. On the other hand, vascular permeability of high-molecular-mass tracers such as FITC-labeled bovine serum albumin and Dextran 70,000 was lower in the CVOs as compared with that in the kidney. Prominent vascular permeability of low- and high-molecular-mass tracers was also observed in the arcuate nucleus. These data demonstrate that vascular permeability for low-molecular-mass molecules is higher in the secretory CVOs as compared with that in the sensory CVOs, possibly for large secretion of peptides to the blood stream. Moreover, vascular permeability for high-molecular-mass tracers in the CVOs is smaller than that of the kidney, indicating that the CVOs are not totally without a BBB.
Collapse
|
45
|
Giuliani D, Minutoli L, Ottani A, Spaccapelo L, Bitto A, Galantucci M, Altavilla D, Squadrito F, Guarini S. Melanocortins as potential therapeutic agents in severe hypoxic conditions. Front Neuroendocrinol 2012; 33:179-93. [PMID: 22531139 DOI: 10.1016/j.yfrne.2012.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 03/26/2012] [Accepted: 04/09/2012] [Indexed: 01/14/2023]
Abstract
Melanocortin peptides with the adrenocorticotropin/melanocyte-stimulating hormone (ACTH/MSH) sequences and synthetic analogs have protective and life-saving effects in experimental conditions of circulatory shock, myocardial ischemia, ischemic stroke, traumatic brain injury, respiratory arrest, renal ischemia, intestinal ischemia and testicular ischemia, as well as in experimental heart transplantation. Moreover, melanocortins improve functional recovery and stimulate neurogenesis in experimental models of cerebral ischemia. These beneficial effects of ACTH/MSH-like peptides are mostly mediated by brain melanocortin MC(3)/MC(4) receptors, whose activation triggers protective pathways that counteract the main ischemia/reperfusion-related mechanisms of damage. Induction of signaling pathways and other molecular regulators of neural stem/progenitor cell proliferation, differentiation and integration seems to be the key mechanism of neurogenesis stimulation. Synthesis of stable and highly selective agonists at MC(3) and MC(4) receptors could provide the potential for development of a new class of drugs for a novel approach to management of severe ischemic diseases.
Collapse
Affiliation(s)
- Daniela Giuliani
- Department of Biomedical Sciences, Section of Pharmacology, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Schreiber S, Bueche CZ, Garz C, Kropf S, Angenstein F, Goldschmidt J, Neumann J, Heinze HJ, Goertler M, Reymann KG, Braun H. The pathologic cascade of cerebrovascular lesions in SHRSP: is erythrocyte accumulation an early phase? J Cereb Blood Flow Metab 2012; 32:278-90. [PMID: 21878945 PMCID: PMC3272595 DOI: 10.1038/jcbfm.2011.122] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cerebral small vessel disease (CSVD) is associated with vessel wall changes, microbleeds, blood-brain barrier (BBB) disturbances, and reduced cerebral blood flow (CBF). As spontaneously hypertensive stroke-prone rats (SHRSP) may be a valid model of some aspects of human CSVD, we aimed to identify whether those changes occur in definite temporal stages and whether there is an initial phenomenon beyond those common vascular alterations. Groups of 51 SHRSP were examined simultaneously by histologic (Hematoxylin-Eosin, IgG-Immunohistochemistry, vessel diameter measurement) and imaging methods (Magnetic Resonance Imaging, 201-Thallium-Diethyldithiocarbamate/99m-Technetium-HMPAO Single Photon Emission Computed Tomography conducted as pilot study) at different stages of age. Vascular pathology in SHRSP proceeds in definite stages, whereas an age-dependent accumulation of erythrocytes in capillaries and arterioles represents the homogeneous initial step of the disease. Erythrocyte accumulations are followed by BBB disturbances and microbleeds, both also increasing with age. Microthromboses, tissue infarctions with CBF reduction, and disturbed potassium uptake represent the final stage of vascular pathology in SHRSP. Erythrocyte accumulations--we parsimoniously interpreted as stases--without cerebral tissue damage represent the first step of vascular pathology in SHRSP. If that initial phenomenon could be identified in patients, these erythrocyte accumulations might be a promising target for implementing prophylactic and therapeutic strategies in human CSVD.
Collapse
Affiliation(s)
- Stefanie Schreiber
- Klinik für Neurologie, Otto-von-Guericke Universität, Magdeburg, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Interrelations between blood-brain barrier permeability and matrix metalloproteinases are differently affected by tissue plasminogen activator and hyperoxia in a rat model of embolic stroke. Med Gas Res 2012; 2:2. [PMID: 22273146 PMCID: PMC3293756 DOI: 10.1186/2045-9912-2-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 01/24/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In ischemic stroke, blood-brain barrier (BBB) regulations, typically involving matrix metalloproteinases (MMPs) and inhibitors (TIMPs) as mediators, became interesting since tissue plasminogen activator (tPA)-related BBB breakdown with risk of secondary hemorrhage was considered to involve these mediators too. Despite high clinical relevance, detailed interactions are purely understood. After a pilot study addressing hyperoxia as potential neuroprotective co-treatment to tPA, we analyzed interrelations between BBB permeability (BBB-P), MMPs and TIMPs. FINDINGS Rats underwent embolic middle cerebral artery occlusion (eMCAO) and treatment with normobaric (NBO) or hyperbaric oxygen (HBO), tPA, tPA+HBO, or no treatment. BBB-P was assessed by intravenously applied FITC-albumin at 4 or 24 hours. MMP-2/-9 and TIMP-1/-2 serum levels were determined at 5 or 25 hours. Time point-corrected partial correlations were used to explore interrelations of BBB-P in ischemic regions (extra-/intravasal FITC-albumin ratio) and related serum markers. BBB-P correlated positively with MMP-2 and MMP-9 in controls, whereas hyperoxia led to an inverse association, most pronounced for HBO/MMP-9 (r = -0.606; P < 0.05). As expected, positive coefficients were observed after treatment with tPA. Co-treatment with HBO attenuated and in part reversed this effect, but to a lower degree than HBO alone. Amongst MMPs and TIMPs, significant associations shifted from MMP-9 to -2 when comparing treatment with HBO/tPA and tPA+HBO. TIMPs were significantly interrelated after tPA, tPA+HBO, and interestingly, HBO alone. CONCLUSIONS HBO was found to reverse the positively directed interrelation of BBB-P and MMPs after eMCAO, but this effect failed to sustain in the expected amount when HBO and tPA were given simultaneously.
Collapse
|
48
|
Abstract
To study spatiotemporal differences in vascular permeability, we histologically analysed tracer extravasation, neovessels and reactive astrocytes in a mouse ischaemic brain damage model. On day 1 after damage induction, the extravasation was not associated with the distribution of neovessels or reactive astrocytes. On day 7, the extravasation was limited within the infarct region in which neovessels, but not reactive astrocytes, were observed. However, the extravasation was not observed at peri-infarct region in which both neovessels and reactive astrocytes were observed, suggesting that neovessels had high permeability and reactive astrocytes prevented the extravasation from neovessels. Furthermore, the extravasation was denser in the regions near the surface than in those further in the infarct region, suggesting a spatial heterogeneity in neovascular permeability.
Collapse
|
49
|
Spaccapelo L, Bitto A, Galantucci M, Ottani A, Irrera N, Minutoli L, Altavilla D, Novellino E, Grieco P, Zaffe D, Squadrito F, Giuliani D, Guarini S. Melanocortin MC₄ receptor agonists counteract late inflammatory and apoptotic responses and improve neuronal functionality after cerebral ischemia. Eur J Pharmacol 2011; 670:479-86. [PMID: 21946115 DOI: 10.1016/j.ejphar.2011.09.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 08/29/2011] [Accepted: 09/07/2011] [Indexed: 01/30/2023]
Abstract
Indirect evidence indicates that, in cerebral ischemia, melanocortins have neuroprotective effects likely mediated by MC₄ receptors. To gain direct insight into the role of melanocortin MC₄ receptors in ischemic stroke, we investigated the effects of a highly selective MC₄ receptor agonist. Gerbils were subjected to transient global cerebral ischemia by occluding both common carotid arteries for 10 min. In saline-treated stroke animals, an impairment in learning and memory occurred that, at day 11 after stroke, was associated with hippocampus up-regulation of tumor necrosis factor-α (TNF-α), BAX, activated extracellular signal-regulated kinases (ERK1/2), c-jun N-terminal kinases (JNK1/2) and caspase-3, down-regulation of Bcl-2, and neuronal loss. Treatment for 11days with the selective melanocortin MC₄ receptor agonist RO27-3225, as well as with the well known non-selective [Nle⁴,D-Phe⁷]α-melanocyte-stimulating hormone (NDP-α-MSH) as a reference non-selective melanocortin, counteracted the inflammatory and apoptotic responses, as indicated by the changes in TNF-α, BAX, ERK1/2, JNK1/2, caspase-3 and Bcl-2 protein expression. Furthermore, melanocortin treatment reduced neuronal loss and dose-dependently improved learning and memory. These positive effects were associated with overexpression of Zif268, an immediate early gene involved in injury repair, synaptic plasticity and memory formation. Pharmacological blockade of MC₄ receptors with the selective MC₄ receptor antagonist HS024 prevented all effects of RO27-3225 and NDP-α-MSH. These data give direct evidence that stimulation of MC₄ receptors affords neuroprotection and promotes functional recovery from stroke, by counteracting prolonged and/or recurrent inflammatory and apoptotic responses, and likely by triggering brain repair pathways.
Collapse
Affiliation(s)
- Luca Spaccapelo
- Department of Biomedical Sciences, Section of Pharmacology, University of Modena and Reggio Emilia, Via G. Campi 287, 41125, Modena, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Alonso A, Reinz E, Fatar M, Hennerici MG, Meairs S. Clearance of albumin following ultrasound-induced blood–brain barrier opening is mediated by glial but not neuronal cells. Brain Res 2011; 1411:9-16. [DOI: 10.1016/j.brainres.2011.07.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/17/2011] [Accepted: 07/05/2011] [Indexed: 01/29/2023]
|