1
|
Li W, Xu P, Kong L, Feng S, Shen N, Huang H, Wang W, Xu X, Wang X, Wang G, Zhang Y, Sun W, Hu W, Liu X. Elabela-APJ axis mediates angiogenesis via YAP/TAZ pathway in cerebral ischemia/reperfusion injury. Transl Res 2023; 257:78-92. [PMID: 36813109 DOI: 10.1016/j.trsl.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 01/13/2023] [Accepted: 02/02/2023] [Indexed: 02/24/2023]
Abstract
Angiogenesis helps to improve neurological recovery by repairing damaged brain tissue and restoring cerebral blood flow (CBF). The role of the Elabela (ELA)-Apelin receptor (APJ) system in angiogenesis has gained much attention. We aimed to investigate the function of endothelial ELA on postischemic cerebral angiogenesis. Here, we demonstrated that the endothelial ELA expression was upregulated in the ischemic brain and treatment with ELA-32 mitigated brain injury and enhanced the restoration of CBF and newly formed functional vessels following cerebral ischemia/reperfusion (I/R) injury. Furthermore, ELA-32 incubation potentiated proliferation, migration, and tube formation abilities of the mouse brain endothelial cells (bEnd.3 cells) under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. RNA sequencing analysis indicated that ELA-32 incubation had a role in the Hippo signaling pathway, and improved angiogenesis-related gene expression in OGD/R-exposed bEnd.3 cells. Mechanistically, we depicted that ELA could bind to APJ and subsequently activate YAP/TAZ signaling pathway. Silence of APJ or pharmacological blockade of YAP abolished the pro-angiogenesis effects of ELA-32. Together, these findings highlight the ELA-APJ axis as a potential therapeutic strategy for ischemic stroke by showing how activation of this pathway promotes poststroke angiogenesis.
Collapse
Affiliation(s)
- Wenyu Li
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Pengfei Xu
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China.
| | - Lingqi Kong
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Shuo Feng
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Nan Shen
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Hongmei Huang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Wuxuan Wang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Xiang Xu
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Xinyue Wang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Guoping Wang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Yan Zhang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Wen Sun
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Wei Hu
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Xinfeng Liu
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| |
Collapse
|
2
|
Mei X, Qiu C, Zhou Q, Chen Z, Chen Y, Xu Z, Zou C. Changes in retinal multilayer thickness and vascular network of patients with Alzheimer's disease. Biomed Eng Online 2021; 20:97. [PMID: 34602087 PMCID: PMC8489058 DOI: 10.1186/s12938-021-00931-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/13/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Retinal biomarkers of Alzheimer's disease (AD) have been extensively investigated in recent decades. Retinal nervous and vascular parameters can reflect brain conditions, and they can facilitate early diagnosis of AD. OBJECTIVE Our study aimed to evaluate the difference in retinal neuro-layer thickness and vascular parameters of patients with AD and healthy controls (HCs). METHODS Non-invasive optical coherence tomography angiography (OCTA) was used to determine the combined thickness of the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL), as well as the full retinal thickness (FRT). The vascular branching (VB), vascular curvature (VC), and vascular density (VD) for AD and HC groups were also obtained. The Mini-Mental State Examination (MMSE) was used to evaluate the cognitive performance of all the participants. After obtaining all the parameters, two-way analysis of variance (ANOVA) was used to compare the mean values of all the retinal parameters of the patients with AD and the HCs. Pearson's correlation was used to test the association between retinal parameters, MMSE scores, and vascular parameters. RESULTS Seventy-eight eyes from 39 participants (19 AD and 20 HC; male, 52.6% in AD and 45.0% in HC; mean [standard deviation] age of 73.79 [7.22] years in AD and 74.35 [6.07] years in HC) were included for the analysis. The average RNFL + GCL thickness (106.32 ± 7.34 μm), FRTs of the four quadrants (290.35 ± 13.05 μm of inferior quadrant, 294.68 ± 9.37 μm of superior quadrant, 302.97 ± 6.52 μm of nasal quadrant, 286.02 ± 13.74 μm of temporal quadrant), and retinal VD (0.0148 ± 0.003) of patients with AD, compared with the HCs, were significantly reduced (p < 0.05). Retinal thickness was significantly correlated with the MMSE scores (p < 0.05). Meanwhile, retinal VD was significantly correlated with the average RNFL + GCL thickness (r2 = 0.2146, p < 0.01). When the vascular parameters were considered, the sensitivity of the AD diagnosis was increased from 0.874 to 0.892. CONCLUSION Our study suggested that the patients with AD, compared with age-matched HCs, had significantly reduced RNFL + GCL thickness and vascular density. These reductions correlated with the cognitive performance of the participants. By combining nerve and vessel parameters, the diagnosis of AD can be improved using OCTA technology. Trail registration Name of the registry: Chinese Clinical Trail Registry, Trial registration number: ChiCTR2000035243, Date of registration: Aug. 5, 2020. URL of trial registry record: http://www.chictr.org.cn/index.aspx.
Collapse
Affiliation(s)
- Xi Mei
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China.
| | - Conglong Qiu
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China
| | - Qi Zhou
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China
| | - Zhongming Chen
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China
| | - Yang Chen
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China
- Ningbo University, Ningbo, Zhejiang, China
| | - Zemin Xu
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China
| | - Chenjun Zou
- Kangning Hospital of Ningbo, Ningbo Kangning Hospital, Zhuangyu South Road 1#, Ningbo, Zhejiang, China.
| |
Collapse
|
3
|
Rakymzhan A, Li Y, Tang P, Wang RK. Differences in cerebral blood vasculature and flow in awake and anesthetized mouse cortex revealed by quantitative optical coherence tomography angiography. J Neurosci Methods 2021; 353:109094. [PMID: 33549637 DOI: 10.1016/j.jneumeth.2021.109094] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 01/27/2021] [Accepted: 01/31/2021] [Indexed: 12/25/2022]
Abstract
BACKGROUND Most of the in vivo neurovascular imaging studies are performed in anesthetized animals. However, anesthesia significantly affects cerebral hemodynamics. NEW METHOD We applied optical coherence tomography (OCT) methods such as optical microangiography (OMAG) and Doppler optical microangiography (DOMAG) to quantitatively evaluate the effect of anesthesia in cerebral vasculature and blood flow in mouse brain. RESULTS The OMAG results indicated the increase of large vessel diameter and capillary density induced by ketamine-xylazine and isoflurane, meaning that both anesthetics caused vasodilation. In addition, the preliminary results from DOMAG showed that isoflurane increased the baseline cerebral blood flow. COMPARISON WITH EXISTING METHODS In comparison with other in vivo imaging modalities, OCT can provide label-free assessment of cortical tissue including tissue morphology, cerebral blood vessel network and flow information down to capillary level, with a large field of view and high imaging speed. CONCLUSIONS OCT angiography methods demonstrated the ability to measure the differences in the baseline morphological and flow parameters of both large and capillary cerebrovascular networks between awake and anesthetized mice.
Collapse
Affiliation(s)
- Adiya Rakymzhan
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| | - Yuandong Li
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| | - Peijun Tang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA.
| |
Collapse
|
4
|
Dolezyczek H, Rapolu M, Niedzwiedziuk P, Karnowski K, Borycki D, Dzwonek J, Wilczynski G, Malinowska M, Wojtkowski M. Longitudinal in-vivo OCM imaging of glioblastoma development in the mouse brain. BIOMEDICAL OPTICS EXPRESS 2020; 11:5003-5016. [PMID: 33014596 PMCID: PMC7510867 DOI: 10.1364/boe.400723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/30/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
We present in-vivo imaging of the mouse brain using custom made Gaussian beam optical coherence microscopy (OCM) with 800nm wavelength. We applied new instrumentation to longitudinal imaging of the glioblastoma (GBM) tumor microvasculature in the mouse brain. We have introduced new morphometric biomarkers that enable quantitative analysis of the development of GBM. We confirmed quantitatively an intensive angiogenesis in the tumor area between 3 and 14 days after GBM cells injection confirmed by considerably increased of morphometric parameters. Moreover, the OCM setup revealed heterogeneity and abnormality of newly formed vessels.
Collapse
Affiliation(s)
- Hubert Dolezyczek
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, ul. Pasteura 3, 02-093 Warsaw, Poland
- both authors contributed equally
| | - Mounika Rapolu
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
- both authors contributed equally
| | - Paulina Niedzwiedziuk
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Karol Karnowski
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Dawid Borycki
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Joanna Dzwonek
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, ul. Pasteura 3, 02-093 Warsaw, Poland
| | - Grzegorz Wilczynski
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, ul. Pasteura 3, 02-093 Warsaw, Poland
| | - Monika Malinowska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, ul. Pasteura 3, 02-093 Warsaw, Poland
| | - Maciej Wojtkowski
- Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
- Baltic Institute of Technology, Al. Zwycięstwa 96/98, 81-451 Gdynia, Poland
- Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Gagarina 11, 87-100 Toruń, Poland
| |
Collapse
|
5
|
Okyere B, Mills WA, Wang X, Chen M, Chen J, Hazy A, Qian Y, Matson JB, Theus MH. EphA4/Tie2 crosstalk regulates leptomeningeal collateral remodeling following ischemic stroke. J Clin Invest 2020; 130:1024-1035. [PMID: 31689239 PMCID: PMC6994159 DOI: 10.1172/jci131493] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/31/2019] [Indexed: 11/17/2022] Open
Abstract
Leptomeningeal anastomoses or pial collateral vessels play a critical role in cerebral blood flow (CBF) restoration following ischemic stroke. The magnitude of this adaptive response is postulated to be controlled by the endothelium, although the underlying molecular mechanisms remain under investigation. Here we demonstrated that endothelial genetic deletion, using EphA4fl/fl/Tie2-Cre and EphA4fl/fl/VeCahderin-CreERT2 mice and vessel painting strategies, implicated EphA4 receptor tyrosine kinase as a major suppressor of pial collateral remodeling, CBF, and functional recovery following permanent middle cerebral artery occlusion. Pial collateral remodeling is limited by the crosstalk between EphA4-Tie2 signaling in vascular endothelial cells, which is mediated through p-Akt regulation. Furthermore, peptide inhibition of EphA4 resulted in acceleration of the pial arteriogenic response. Our findings demonstrate that EphA4 is a negative regulator of Tie2 receptor signaling, which limits pial collateral arteriogenesis following cerebrovascular occlusion. Therapeutic targeting of EphA4 and/or Tie2 represents an attractive new strategy for improving collateral function, neural tissue health, and functional recovery following ischemic stroke.
Collapse
Affiliation(s)
| | - William A. Mills
- School of Neuroscience
- Graduate Program in Translational Biology, Medicine, and Health
| | - Xia Wang
- Department of Biomedical Sciences and Pathobiology
| | - Michael Chen
- Department of Biomedical Sciences and Pathobiology
| | - Jiang Chen
- Department of Biomedical Sciences and Pathobiology
| | - Amanda Hazy
- Department of Biomedical Sciences and Pathobiology
| | - Yun Qian
- Department of Mechanical Engineering
- Center for Drug Discovery
| | | | - Michelle H. Theus
- Department of Biomedical Sciences and Pathobiology
- School of Neuroscience
- Center for Regenerative Medicine, College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
| |
Collapse
|
6
|
Yang S, Liu K, Yao L, Liu K, Weng G, Xu K, Li P. Correlation of optical attenuation coefficient estimated using optical coherence tomography with changes in astrocytes and neurons in a chronic photothrombosis stroke model. BIOMEDICAL OPTICS EXPRESS 2019; 10:6258-6271. [PMID: 31853398 PMCID: PMC6913389 DOI: 10.1364/boe.10.006258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/09/2019] [Accepted: 11/10/2019] [Indexed: 06/02/2023]
Abstract
The optical attenuation coefficient (OAC) estimated using optical coherence tomography (OAC-OCT) offers a label-free 3D mapping of tissue infarction, but the physiological origin of the OAC contrast remains unclear. For effectively suppressing OAC fluctuations, we propose a hybrid (wavelength/angle) division multiplexing (HDM) method, which improved the OAC contrast by 70.7% in tissue phantoms. To test the feasibility of OAC-based infarction detection, triphenyltetrazolium chloride (TTC) staining was performed on fresh ex vivo brain slices, and the TTC-defined infarction was used as the ground truth. Sharp OAC contrast was observed between the TTC-defined infarction (1.09 mm-1) and normal tissue (0.79 mm-1). The OAC infarction spatially matched well with the TTC-defined infarction. To further explore the physiological origin of OAC contrast in ischemic stroke at the cellular level, the dynamic changes in OAC were measured in the rat cortex in vivo over 3 weeks after photothrombosis (PT) occlusion and found significantly correlated with the changes in astrocytes and neurons acquired with ex vivo hematoxylin and eosin (HE), glial fibrillary acidic protein (GFAP), and NeuN staining. These results suggest that OAC imaging enables non-invasive infarction detection and its contrast might originate from the changes in astrocytes and neurons in the chronic PT stroke model. The cellular responses revealed by in vivo OAC imaging would be essential for evaluating treatments and even developing novel therapies.
Collapse
Affiliation(s)
- Shanshan Yang
- State Key Lab of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Kezhou Liu
- Department of Biomedical Engineering, Key Laboratory of Biomedical Engineering of Education Ministry, Zhejiang University, Hangzhou, Zhejiang 310027, China
- College of Artificial Intelligence, Dept. of Biomedical Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Lin Yao
- State Key Lab of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Kaiyuan Liu
- State Key Lab of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Guoqing Weng
- College of Artificial Intelligence, Dept. of Biomedical Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China
| | - Kedi Xu
- Qiushi Academy for Advanced Studies (QAAS), Zhejiang University, Hangzhou, Zhejiang 310027, China
- Department of Biomedical Engineering, Key Laboratory of Biomedical Engineering of Education Ministry, Zhejiang University, Hangzhou, Zhejiang 310027, China
- Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Peng Li
- State Key Lab of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| |
Collapse
|
7
|
Methner C, Mishra A, Golgotiu K, Li Y, Wei W, Yanez ND, Zlokovic B, Wang RK, Alkayed NJ, Kaul S, Iliff JJ. Pericyte constriction underlies capillary derecruitment during hyperemia in the setting of arterial stenosis. Am J Physiol Heart Circ Physiol 2019; 317:H255-H263. [PMID: 31125259 DOI: 10.1152/ajpheart.00097.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Capillary derecruitment distal to a coronary stenosis is implicated as the mechanism of reversible perfusion defect and potential myocardial ischemia during coronary hyperemia; however, the underlying mechanisms are not defined. We tested whether pericyte constriction underlies capillary derecruitment during hyperemia under conditions of stenosis. In vivo two-photon microscopy (2PM) and optical microangiography (OMAG) were used to measure hyperemia-induced changes in capillary diameter and perfusion in wild-type and pericyte-depleted mice with femoral artery stenosis. OMAG demonstrated that hyperemic challenge under stenosis produced capillary derecruitment associated with decreased RBC flux. 2PM demonstrated that hyperemia under control conditions induces 26 ± 5% of capillaries to dilate and 19 ± 3% to constrict. After stenosis, the proportion of capillaries dilating to hyperemia decreased to 14 ± 4% (P = 0.05), whereas proportion of constricting capillaries increased to 32 ± 4% (P = 0.05). Hyperemia-induced changes in capillary diameter occurred preferentially in capillary segments invested with pericytes. In a transgenic mouse model featuring partial pericyte depletion, only 14 ± 3% of capillaries constricted to hyperemic challenge after stenosis, a significant reduction from 33 ± 4% in wild-type littermate controls (P = 0.04). These results provide for the first time direct visualization of hyperemia-induced capillary derecruitment distal to arterial stenosis and demonstrate that pericyte constriction underlies this phenomenon in vivo. These results could have important therapeutic implications in the treatment of exercise-induced ischemia. NEW & NOTEWORTHY In the setting of coronary arterial stenosis, hyperemia produces a reversible perfusion defect resulting from capillary derecruitment that is believed to underlie cardiac ischemia under hyperemic conditions. We use optical microangiography and in vivo two-photon microscopy to visualize capillary derecruitment distal to a femoral arterial stenosis with cellular resolution. We demonstrate that capillary constriction in response to hyperemia in the setting of stenosis is dependent on pericytes, contractile mural cells investing the microcirculation.
Collapse
Affiliation(s)
- Carmen Methner
- Knight Cardiovascular Institute, Oregon Health & Science University , Portland, Oregon
| | - Anusha Mishra
- Knight Cardiovascular Institute, Oregon Health & Science University , Portland, Oregon
| | - Kirsti Golgotiu
- Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University , Portland, Oregon
| | - Yuandong Li
- Department of Bioengineering, University of Washington , Seattle, Washington
| | - Wei Wei
- Department of Bioengineering, University of Washington , Seattle, Washington
| | - N David Yanez
- Division of Biostatistics, School of Public Health, Oregon Health & Science University , Portland, Oregon
| | - Berislav Zlokovic
- Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington , Seattle, Washington
| | - Nabil J Alkayed
- Knight Cardiovascular Institute, Oregon Health & Science University , Portland, Oregon.,Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University , Portland, Oregon
| | - Sanjiv Kaul
- Knight Cardiovascular Institute, Oregon Health & Science University , Portland, Oregon
| | - Jeffrey J Iliff
- Knight Cardiovascular Institute, Oregon Health & Science University , Portland, Oregon.,Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University , Portland, Oregon
| |
Collapse
|
8
|
McEnaney RM, McCreary D, Tzeng E. A modified rat model of hindlimb ischemia for augmentation and functional measurement of arteriogenesis. J Biol Methods 2018; 5:e89. [PMID: 31435496 PMCID: PMC6703558 DOI: 10.14440/jbm.2018.234] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Arteriogenesis (collateral artery development) is an adaptive pathway critical for salvage of tissue in the setting of arterial occlusion. Rodent models of arteriogenesis typically involve an experimental occlusion (ligation) of a hindlimb artery and then rely on indirect measures such as laser Doppler perfusion imaging to assess blood flow recovery. Unfortunately, the more commonly utilized measures of distal tissue perfusion at rest are unable to account for hemodynamic and vasoactive variables and thus provide an incomplete assessment of collateral network capacity. We provide a detailed description of modifications to the commonly used model of femoral artery ligation. These serve to alter and then directly assess collateral network's hemodynamic capacity. By incorporating an arteriovenous fistula distal to the arterial ligation, arterial growth is maximized. Hindlimb perfusion may be isolated to measure minimum resistance of flow around the arterial occlusion, which provides a direct measure of collateral network capacity. Our results reinforce that arteriogenesis is driven by hemodynamic variables, and it can be reliably augmented and measured in absolute terms. Using these modifications to a widely used model, functional arteriogenesis may be more directly studied.
Collapse
Affiliation(s)
- Ryan M McEnaney
- Department of Surgery, University of Pittsburgh School of Medicine.,Veterans Affairs Pittsburgh Healthcare System
| | | | - Edith Tzeng
- Department of Surgery, University of Pittsburgh School of Medicine.,Veterans Affairs Pittsburgh Healthcare System
| |
Collapse
|
9
|
Li Y, Wei W, Wang RK. Capillary flow homogenization during functional activation revealed by optical coherence tomography angiography based capillary velocimetry. Sci Rep 2018. [PMID: 29515156 PMCID: PMC5841298 DOI: 10.1038/s41598-018-22513-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Elaborate modeling study suggests an important role of capillary transit time heterogeneity (CTTH) reduction in brain oxygenation during functional hyperemia. Here, we use optical coherence tomography angiography (OCTA) capillary velocimetry to probe blood flow dynamics in cerebral capillary beds and validate the change in CTTH during functional activation in an in vivo rodent model. Through evaluating flow dynamics and consequent transit time parameters from thousands of capillary vessels within three-dimensional (3-D) tissue volume upon hindpaw electrical stimulation, we observe reductions in both capillary mean transit time (MTT) (9.8% ± 2.2) and CTTH (5.9% ± 1.4) in the hindlimb somatosensory cortex (HLS1). Additionally, capillary flow pattern modification is observed with a significant difference (p < 0.05) between the HLS1 and non-activated cortex regions. These quantitative findings reveal a localized microcirculatory adjustment during functional activation, consistent with previous studies, and support the critical contribution of capillary flow homogenization to brain oxygenation. The OCTA velocimetry is a useful tool to image microcirculatory dynamics in vivo using animal models, enabling a more comprehensive understanding as to hemodynamic-metabolic coupling.
Collapse
Affiliation(s)
- Yuandong Li
- Department of Bioengineering, University of Washington, Seattle, USA
| | - Wei Wei
- Department of Bioengineering, University of Washington, Seattle, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, USA.
| |
Collapse
|
10
|
Okyere B, Creasey M, Lebovitz Y, Theus MH. Temporal remodeling of pial collaterals and functional deficits in a murine model of ischemic stroke. J Neurosci Methods 2018; 293:86-96. [PMID: 28935424 PMCID: PMC5749401 DOI: 10.1016/j.jneumeth.2017.09.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/14/2017] [Accepted: 09/16/2017] [Indexed: 12/17/2022]
Abstract
BACKGROUND Leptomeningeal anastomoses play a critical role in regulating reperfusion following cerebrovascular obstruction; however, methods to evaluate their temporospatial remodeling remains under investigation. NEW METHOD We combined arteriole-specific vessel painting with histological evaluation to assess the density and diameter of inter-collateral vessels between the middle cerebral artery and anterior cerebral artery (MCA-ACA) or posterior cerebral artery (MCA-PCA) in a murine model of permanent middle cerebral artery occlusion (pMCAO). RESULTS While the overall density was not influenced by pMCAO, the size of MCA-ACA and MCA-PCA vessels had significantly increased 2days post-pMCAO and peaked by 4days compared to the un-injured hemisphere. Using a combination of vessel painting and immunofluorescence, we uniquely observed an induction of cellular division and a remodeling of the smooth muscle cells within the collateral niche following post-pMCAO on whole mount tissue sections. Vessel painting was also applied to pMCAO-injured Cx3cr1GFP mice, in order to identify the spatial relationship between Cx3cr1-positive peripheral-derived monocyte/macrophages and the vessel painted collaterals. Our histological findings were supplemented with analysis of cerebral blood flow using laser Doppler imaging and behavioral changes following pMCAO. COMPARISON WITH EXISTING METHODS Compared to polyurethane and latex methods for collateral labeling, this new method provides detailed cell-type specific analysis within the collateral niche at the microscopic level, which has previously been unavailable. CONCLUSIONS This simple and reproducible combination of techniques is the first to dissect the temporospatial remodeling of pial collateral arterioles. The method will advance investigations into the underlying mechanisms governing the intricate processes of arteriogenesis.
Collapse
Affiliation(s)
- Benjamin Okyere
- The Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, 970 Washington St. SW, Blacksburg, VA, 24061, USA
| | - Miranda Creasey
- The Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, 970 Washington St. SW, Blacksburg, VA, 24061, USA
| | - Yeonwoo Lebovitz
- The Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, 970 Washington St. SW, Blacksburg, VA, 24061, USA
| | - Michelle H Theus
- The Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, 970 Washington St. SW, Blacksburg, VA, 24061, USA.
| |
Collapse
|