1
|
Tokudome T, Otani K, Mao Y, Jensen LJ, Arai Y, Miyazaki T, Sonobe T, Pearson JT, Osaki T, Minamino N, Ishida J, Fukamizu A, Kawakami H, Onozuka D, Nishimura K, Miyazato M, Nishimura H. Endothelial Natriuretic Peptide Receptor 1 Play Crucial Role for Acute and Chronic Blood Pressure Regulation by Atrial Natriuretic Peptide. Hypertension 2022; 79:1409-1422. [PMID: 35534926 DOI: 10.1161/hypertensionaha.121.18114] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND ANP (atrial natriuretic peptide), acting through NPR1 (natriuretic peptide receptor 1), provokes hypotension. Such hypotension is thought to be due to ANP inducing vasodilation via NPR1 in the vasculature; however, the underlying mechanism remains unclear. Here, we investigated the mechanisms of acute and chronic blood pressure regulation by ANP. METHODS AND RESULTS Immunohistochemical analysis of rat tissues revealed that NPR1 was abundantly expressed in endothelial cells and smooth muscle cells of small arteries and arterioles. Intravenous infusion of ANP significantly lowered systolic blood pressure in wild-type mice. ANP also significantly lowered systolic blood pressure in smooth muscle cell-specific Npr1-knockout mice but not in endothelial cell-specific Npr1-knockout mice. Moreover, ANP significantly lowered systolic blood pressure in Nos3-knockout mice. In human umbilical vein endothelial cells, treatment with ANP did not influence nitric oxide production or intracellular Ca2+ concentration, but it did hyperpolarize the cells. ANP-induced hyperpolarization of human umbilical vein endothelial cells was inhibited by several potassium channel blockers and was also abolished under knockdown of RGS2 (regulator of G-protein signaling 2), an GTPase activating protein in G-protein α-subunit. ANP increased Rgs2 mRNA expression in human umbilical vein endothelial cells but failed to lower systolic blood pressure in Rgs2-knockout mice. Endothelial cell-specific Npr1-overexpressing mice exhibited lower blood pressure than did wild-type mice independent of RGS2, and showed dilation of arterial vessels on synchrotron radiation microangiography. CONCLUSIONS Together, these results indicate that vascular endothelial NPR1 plays a crucial role in ANP-mediated blood pressure regulation, presumably by a mechanism that is RGS2-dependent in the acute phase and RGS2-independent in the chronic phase.
Collapse
Affiliation(s)
- Takeshi Tokudome
- Department of Biochemistry (T.T., Y.M., N.M., M.M., H.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Kentaro Otani
- Department of Regenerative Medicine and Tissue Engineering (K.O.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Yuanjie Mao
- Department of Biochemistry (T.T., Y.M., N.M., M.M., H.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.,Diabetes Institute, Ohio University, Athens (Y.M.)
| | - Lars Jørn Jensen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark (L.J.J.)
| | - Yuji Arai
- Department of Research Promotion and Management (Y.A.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Takahiro Miyazaki
- Department of Cell Biology (T.M.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Takashi Sonobe
- Department of Cardiac Physiology (T.S., J.T.P.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - James T Pearson
- Department of Cardiac Physiology (T.S., J.T.P.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.,Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Australia (J.T.P.)
| | - Tsukasa Osaki
- Department of Biochemistry and Molecular Biology, Yamagata University School of Medicine, Japan (T.O.)
| | - Naoto Minamino
- Department of Biochemistry (T.T., Y.M., N.M., M.M., H.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Junji Ishida
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Ibaraki, Japan (J.I., A.F.)
| | - Akiyoshi Fukamizu
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Ibaraki, Japan (J.I., A.F.)
| | - Hayato Kawakami
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan (H.K.)
| | - Daisuke Onozuka
- Department of Medical Informatics and Clinical Epidemiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Japan (D.O.)
| | - Kunihiro Nishimura
- Department of Preventive Medicine and Epidemiology (K.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Mikiya Miyazato
- Department of Biochemistry (T.T., Y.M., N.M., M.M., H.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Hirohito Nishimura
- Department of Biochemistry (T.T., Y.M., N.M., M.M., H.N.), National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| |
Collapse
|
2
|
Sonobe T, Tsuchimochi H, Maeda H, Pearson JT. Increased contribution of KCa channels to muscle contraction induced vascular and blood flow responses in sedentary and exercise trained ZFDM rats. J Physiol 2022; 600:2919-2938. [PMID: 35551673 DOI: 10.1113/jp282981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/04/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Microvascular dysfunction in type 2 diabetes impairs blood flow redistribution during exercise and limits the performance of skeletal muscle and may cause early fatigability. Endothelium-dependent hyperpolarization (EDH), which mediates vasodilation in resistance arteries is known to be depressed in animals with diabetes. Here we report that low-intensity exercise training in ZFDM rats increased KCa channel-derived component in the vasodilator responses to muscle contraction than in sedentary rats, partly due to the increase in KCNN3 expression. These results suggest that low-intensity exercise training improves blood flow redistribution in contracting skeletal muscle in metabolic disease with diabetes via upregulation of EDH. ABSTRACT In resistance arteries, endothelium-dependent hyperpolarization (EDH) mediated vasodilation is depressed in diabetes. We hypothesized that downregulation of KCa channel derived EDH reduces exercise-induced vasodilation and blood flow redistribution in diabetes. To test this hypothesis, we evaluated vascular function in response to hindlimb muscle contraction, and the contribution of KCa channels in anaesthetised ZFDM, metabolic disease rats with type 2 diabetes. We also tested whether exercise training ameliorated the vascular response. Using in vivo microangiography, the hindlimb vasculature was visualized before and after rhythmic muscle contraction (0.5 s tetanus every 3 sec, 20 times) evoked by sciatic nerve stimulation (40 Hz). Femoral blood flow of the contracting hindlimb was simultaneously measured by an ultrasonic flowmeter. The contribution of KCa channels was investigated in the presence and absence of apamin and charybdotoxin. We found that vascular and blood flow responses to muscle contraction were significantly impaired at the level of small artery segments in ZFDM fa/fa rats compared to its lean control fa/+ rats. The contribution of KCa channels was also smaller in fa/fa than in fa/+ rats. Low-intensity exercise training for 12 weeks in fa/fa rats demonstrated minor changes in the vascular and blood flow response to muscle contraction. However, KCa-derived component in the response to muscle contraction was much greater in exercise trained than in sedentary fa/fa rats. These data suggest that exercise training increases the contribution of KCa channels among endothelium-dependent vasodilatory mechanisms to maintain vascular and blood flow responses to muscle contraction in this metabolic disease rat model. Abstract figure legend Low-intensity exercise training in ZFDM, metabolic disease rats with type 2 diabetes increases KCa channel-derived component of endothelium-dependent hyperpolarization in the vascular and blood flow responses to skeletal muscle contraction than the responses in sedentary rats, partly due to upregulation of KCNN3 protein expression. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Takashi Sonobe
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - Hisashi Maeda
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.,Victoria Heart Institute and Monash Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, Australia
| |
Collapse
|
3
|
Synchrotron X-ray Radiation (SXR) in Medical Imaging: Current Status and Future Prospects. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12083790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Synchrotron X-ray radiation (SXR) has been widely studied to explore the structure of matter. Recently, there has been an intense focus on the medical application of SXR in imaging. This review is intended to explore the latest applications of SXR in medical imaging and to shed light on the advantages and drawbacks of this modality. The article highlights the latest developments in other fields that can greatly enhance the capability and applicability of SXR. The potentials of using machine and deep learning (DL)-based methods to generate synthetic images to use in regular clinics along with the use of photon counting X-ray detectors for spectral medical imaging with SXR are also discussed.
Collapse
|
4
|
Ma W, Gong H, Jani V, Lee KH, Landim-Vieira M, Papadaki M, Pinto JR, Aslam MI, Cammarato A, Irving T. Myofibril orientation as a metric for characterizing heart disease. Biophys J 2022; 121:565-574. [PMID: 35032456 PMCID: PMC8874025 DOI: 10.1016/j.bpj.2022.01.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/28/2021] [Accepted: 01/11/2022] [Indexed: 11/17/2022] Open
Abstract
Myocyte disarray is a hallmark of many cardiac disorders. However, the relationship between alterations in the orientation of individual myofibrils and myofilaments to disease progression has been largely underexplored. This oversight has predominantly been because of a paucity of methods for objective and quantitative analysis. Here, we introduce a novel, less-biased approach to quantify myofibrillar and myofilament orientation in cardiac muscle under near-physiological conditions and demonstrate its superiority as compared with conventional histological assessments. Using small-angle x-ray diffraction, we first investigated changes in myofibrillar orientation at increasing sarcomere lengths in permeabilized, relaxed, wild-type mouse myocardium from the left ventricle by assessing the angular spread of the 1,0 equatorial reflection (angle σ). At a sarcomere length of 1.9 μm, the angle σ was 0.23 ± 0.01 rad, decreased to 0.19 ± 0.01 rad at a sarcomere length of 2.1 μm, and further decreased to 0.15 ± 0.01 rad at a sarcomere length of 2.3 μm (p < 0.0001). Angle σ was significantly larger in R403Q, a MYH7 hypertrophic cardiomyopathy model, porcine myocardium (0.24 ± 0.01 rad) compared with wild-type myocardium (0.14 ± 0.005 rad; p < 0.0001), as well as in human heart failure tissue (0.19 ± 0.006 rad) when compared with nonfailing samples (0.17 ± 0.007 rad; p = 0.01). These data indicate that diseased myocardium suffers from greater myofibrillar disorientation compared with healthy controls. Finally, we showed that conventional, histology-based analysis of disarray can be subject to user bias and/or sampling error and lead to false positives. Our method for directly assessing myofibrillar orientation avoids the artifacts introduced by conventional histological approaches that assess myocyte orientation and only indirectly evaluate myofibrillar orientation, and provides a precise and objective metric for phenotypically characterizing myocardium. The ability to obtain excellent x-ray diffraction patterns from frozen human myocardium provides a new tool for investigating structural anomalies associated with cardiac diseases.
Collapse
Affiliation(s)
- Weikang Ma
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, Illinois.
| | - Henry Gong
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, Illinois
| | - Vivek Jani
- Department of Biomedical Engineering, The Johns Hopkins School of Medicine, The Johns Hopkins University, Baltimore, Maryland; Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Kyoung Hwan Lee
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Maicon Landim-Vieira
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida
| | - Maria Papadaki
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, Illinois
| | - Jose R Pinto
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida
| | - M Imran Aslam
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Anthony Cammarato
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Thomas Irving
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, Illinois
| |
Collapse
|
5
|
Inocencio IM, Tran NT, Nakamura S, Khor SJ, Wiersma M, Stoecker K, Maksimenko A, Polglase GR, Walker DW, Pearson JT, Wong FY. Cerebral haemodynamic response to somatosensory stimulation in preterm lambs and 7-10-day old lambs born at term: Direct synchrotron microangiography assessment. J Cereb Blood Flow Metab 2022; 42:315-328. [PMID: 34551607 PMCID: PMC9122524 DOI: 10.1177/0271678x211045848] [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] [Indexed: 11/16/2022]
Abstract
Neurovascular coupling has been well-defined in the adult brain, but variable and inconsistent responses have been observed in the neonatal brain. The mechanisms that underlie functional haemodynamic responses in the developing brain are unknown. Synchrotron radiation (SR) microangiography enables in vivo high-resolution imaging of the cerebral vasculature. We exploited SR microangiography to investigate the microvascular changes underlying the cerebral haemodynamic response in preterm (n = 7) and 7-10-day old term lambs (n = 4), following median nerve stimulation of 1.8, 4.8 and 7.8 sec durations.Increasing durations of somatosensory stimulation significantly increased the number of cortical microvessels of ≤200 µm diameter in 7-10-day old term lambs (p < 0.05) but not preterm lambs where, in contrast, stimulation increased the diameter of cerebral microvessels with a baseline diameter of ≤200 µm. Preterm lambs demonstrated positive functional responses with increased oxyhaemoglobin measured by near infrared spectroscopy, while 7-10-day old term lambs demonstrated both positive and negative responses. Our findings suggest the vascular mechanisms underlying the functional haemodynamic response differ between the preterm and 7-10-day old term brain. The preterm brain depends on vasodilatation of microvessels without recruitment of additional vessels, suggesting a limited capacity to mount higher cerebral haemodynamic responses when faced with prolonged or stronger neural stimulation.
Collapse
Affiliation(s)
- Ishmael M Inocencio
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia.,*Co-first authors who contributed equally to this work
| | - Nhi T Tran
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia.,School of Health & Biomedical Sciences, RMIT University, Melbourne, Australia.,*Co-first authors who contributed equally to this work
| | - Shinji Nakamura
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Song J Khor
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| | - Manon Wiersma
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| | - Katja Stoecker
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| | - Anton Maksimenko
- Imaging and Medical Beamline, Australian Synchrotron, ANSTO, Melbourne, Australia
| | - Graeme R Polglase
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - David W Walker
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,School of Health & Biomedical Sciences, RMIT University, Melbourne, Australia
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Centre, Osaka, Japan.,Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Flora Y Wong
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia.,Monash Newborn, Monash Children's Hospital, Melbourne, Australia
| |
Collapse
|
6
|
Waddingham MT, Tsuchimochi H, Sonobe T, Asano R, Jin H, Ow CPC, Schwenke DO, Katare R, Aoyama K, Umetani K, Hoshino M, Uesugi K, Shirai M, Ogo T, Pearson JT. Using Synchrotron Radiation Imaging Techniques to Elucidate the Actions of Hexarelin in the Heart of Small Animal Models. Front Physiol 2022; 12:766818. [PMID: 35126171 PMCID: PMC8814524 DOI: 10.3389/fphys.2021.766818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/23/2021] [Indexed: 11/13/2022] Open
Abstract
The majority of the conventional techniques that are utilized for investigating the pathogenesis of cardiovascular disease in preclinical animal models do not permit microlevel assessment of in situ cardiomyocyte and microvascular functions. Therefore, it has been difficult to establish whether cardiac dysfunction in complex multiorgan disease states, such as heart failure with preserved ejection fraction and pulmonary hypertension, have their origins in microvascular dysfunction or rather in the cardiomyocyte. Herein, we describe our approach of utilizing synchrotron radiation microangiography to, first, ascertain whether the growth hormone secretagogue (GHS) hexarelin is a vasodilator in the coronary circulation of normal and anesthetized Sprague-Dawley rats, and next investigate if hexarelin is able to prevent the pathogenesis of right ventricle (RV) dysfunction in pulmonary hypertension in the sugen chronic hypoxia model rat. We show that acute hexarelin administration evokes coronary microvascular dilation through GHS-receptor 1a and nitric oxide, and through endothelium-derived hyperpolarization. Previous work indicated that chronic exogenous administration of ghrelin largely prevented the pathogenesis of pulmonary hypertension in chronic hypoxia and in monocrotaline models. Unexpectedly, chronic hexarelin administration prior to sugen chronic hypoxia did not prevent RV hypertrophy or RV cardiomyocyte relaxation impairment. Small-angle X-ray scattering revealed that super relaxed myosin filaments contributed to diastolic dysfunction, and that length-dependent activation might contribute to sustained contractility of the RV. Thus, synchrotron-based imaging approaches can reveal novel insights into cardiac and coronary functions in vivo.
Collapse
Affiliation(s)
- Mark T. Waddingham
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Takashi Sonobe
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Ryotaro Asano
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Huiling Jin
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Connie P. C. Ow
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Daryl O. Schwenke
- Department of Physiology, School of Biomedical Sciences, Heart Otago, University of Otago, Dunedin, New Zealand
| | - Rajesh Katare
- Department of Physiology, School of Biomedical Sciences, Heart Otago, University of Otago, Dunedin, New Zealand
| | - Kohki Aoyama
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Masato Hoshino
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Kentaro Uesugi
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Mikiyasu Shirai
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center, Suita, Japan
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Takeshi Ogo
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center, Suita, Japan
| | - James T. Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- *Correspondence: James T. Pearson
| |
Collapse
|
7
|
Inagaki T, Pearson JT, Tsuchimochi H, Schwenke DO, Saito S, Higuchi T, Masaki T, Umetani K, Shirai M, Nakaoka Y. Evaluation of right coronary vascular dysfunction in severe pulmonary hypertensive rats using synchrotron radiation microangiography. Am J Physiol Heart Circ Physiol 2021; 320:H1021-H1036. [PMID: 33481696 DOI: 10.1152/ajpheart.00327.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 01/06/2021] [Accepted: 01/06/2021] [Indexed: 11/22/2022]
Abstract
Pulmonary hypertension (PH) causes cardiac hypertrophy in the right ventricle (RV) and eventually leads to RV failure due to persistently elevated ventricular afterload. We hypothesized that the mechanical stress on the RV associated with increased afterload impairs vasodilator function of the right coronary artery (RCA) in PH. Coronary vascular response was assessed using microangiography with synchrotron radiation (SR) in two well-established PH rat models, monocrotaline injection or the combined exposure to chronic hypoxia and vascular endothelial growth factor receptor blockade with Su5416 (SuHx model). In the SuHx model, the effect of the treatment with the nonselective endothelin-1 receptor antagonist (ERA), macitentan, was also examined. Myocardial viability was determined in SuHx model rats, using 18F-FDG Positron emission tomography (PET) and magnetic resonance imaging (MRI). Endothelium-dependent and endothelium-independent vasodilator responses were significantly attenuated in the medium and small arteries of severe PH rats. ERA treatment significantly improved RCA vascular function compared with the untreated group. ERA treatment improved both the decrease in ejection fraction and the increased glucose uptake, and reduced RV remodeling. In addition, the upregulation of inflammatory genes in the RV was almost suppressed by ERA treatment. We found impairment of vasodilator responses in the RCA of severe PH rat models. Endothelin-1 activation in the RCA plays a major role in impaired vascular function in PH rats and is partially restored by ERA treatment. Treatment of PH with ERA may improve RV function in part by indirectly attenuating right heart afterload and in part by associated improvements in right coronary endothelial function.NEW & NOTEWORTHY We demonstrated for the first time the impairment of vascular responses in the right coronary artery (RCA) of the dysfunctional right heart in pulmonary hypertensive rats in vivo. Treatment with an endothelin-1 receptor antagonist ameliorated vascular dysfunction in the RCA, enabled tissue remodeling of the right heart, and improved cardiac function. Our results suggest that impaired RCA function might also contribute to the early progression to heart failure in patients with severe pulmonary arterial hypertension (PAH). The endothelium of the coronary vasculature might be considered as a potential target in treatments to prevent heart failure in severe patients with PAH.
Collapse
MESH Headings
- Animals
- Antihypertensive Agents/pharmacology
- Coronary Angiography
- Coronary Vessels/diagnostic imaging
- Coronary Vessels/drug effects
- Coronary Vessels/metabolism
- Coronary Vessels/physiopathology
- Disease Models, Animal
- Endothelin Receptor Antagonists/pharmacology
- Endothelin-1/genetics
- Endothelin-1/metabolism
- Hypertrophy, Right Ventricular/diagnostic imaging
- Hypertrophy, Right Ventricular/drug therapy
- Hypertrophy, Right Ventricular/metabolism
- Hypertrophy, Right Ventricular/physiopathology
- Hypoxia/complications
- Indoles
- Monocrotaline
- Predictive Value of Tests
- Pulmonary Arterial Hypertension/diagnostic imaging
- Pulmonary Arterial Hypertension/drug therapy
- Pulmonary Arterial Hypertension/metabolism
- Pulmonary Arterial Hypertension/physiopathology
- Pyrimidines/pharmacology
- Pyrroles
- Rats, Sprague-Dawley
- Severity of Illness Index
- Sulfonamides/pharmacology
- Synchrotrons
- Vasodilation/drug effects
- Ventricular Dysfunction, Right/diagnostic imaging
- Ventricular Dysfunction, Right/drug therapy
- Ventricular Dysfunction, Right/metabolism
- Ventricular Dysfunction, Right/physiopathology
- Ventricular Function, Right
- Ventricular Remodeling
- Rats
Collapse
Affiliation(s)
- Tadakatsu Inagaki
- Department of Vascular Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
- Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Australia
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Daryl O Schwenke
- Department of Physiology Heart-Otago, University of Otago, Dunedin, New Zealand
| | - Shigeyoshi Saito
- Department of Bio_Medical Imaging, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Takahiro Higuchi
- Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Takeshi Masaki
- Department of Vascular Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Yoshikazu Nakaoka
- Department of Vascular Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| |
Collapse
|
8
|
β-blockade prevents coronary macro- and microvascular dysfunction induced by a high salt diet and insulin resistance in the Goto-Kakizaki rat. Clin Sci (Lond) 2021; 135:327-346. [PMID: 33480422 DOI: 10.1042/cs20201441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 01/01/2023]
Abstract
A high salt intake exacerbates insulin resistance, evoking hypertension due to systemic perivascular inflammation, oxidative-nitrosative stress and endothelial dysfunction. Angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blockers (ARBs) have been shown to abolish inflammation and redox stress but only partially restore endothelial function in mesenteric vessels. We investigated whether sympatho-adrenal overactivation evokes coronary vascular dysfunction when a high salt intake is combined with insulin resistance in male Goto-Kakizaki (GK) and Wistar rats treated with two different classes of β-blocker or vehicle, utilising synchrotron-based microangiography in vivo. Further, we examined if chronic carvedilol (CAR) treatment preserves nitric oxide (NO)-mediated coronary dilation more than metoprolol (MET). A high salt diet (6% NaCl w/w) exacerbated coronary microvessel endothelial dysfunction and NO-resistance in vehicle-treated GK rats while Wistar rats showed modest impairment. Microvascular dysfunction was associated with elevated expression of myocardial endothelin, inducible NO synthase (NOS) protein and 3-nitrotyrosine (3-NT). Both CAR and MET reduced basal coronary perfusion but restored microvessel endothelium-dependent and -independent dilation indicating a role for sympatho-adrenal overactivation in vehicle-treated rats. While MET treatment reduced myocardial nitrates, only MET treatment completely restored microvessel dilation to dobutamine (DOB) stimulation in the absence of NO and prostanoids (combined inhibition), indicating that MET restored the coronary flow reserve attributable to endothelium-derived hyperpolarisation (EDH). In conclusion, sympatho-adrenal overactivation caused by high salt intake and insulin resistance evoked coronary microvessel endothelial dysfunction and diminished NO sensitivity, which were restored by MET and CAR treatment in spite of ongoing inflammation and oxidative-nitrosative stress presumably caused by uninhibited renin-angiotensin-aldosterone system (RAAS) overactivation.
Collapse
|
9
|
Inocencio IM, Tran NT, Nakamura S, Khor SJ, Wiersma M, Stoecker K, Polglase GR, Pearson JT, Wong FY. Increased peak end-expiratory pressure in ventilated preterm lambs changes cerebral microvascular perfusion: direct synchrotron microangiography assessment. J Appl Physiol (1985) 2020; 129:1075-1084. [PMID: 32909920 DOI: 10.1152/japplphysiol.00652.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Positive end-expiratory pressure (PEEP) improves oxygenation in mechanically ventilated preterm neonates by preventing lung collapse. However, high PEEP may alter cerebral blood flow secondarily to the increased intrathoracic pressure, predisposing to brain injury. The precise effects of high PEEP on cerebral hemodynamics in the preterm brain are unknown. We aimed to assess the effect of PEEP on microvessels in the preterm brain by using synchrotron radiation (SR) microangiography, which enables in vivo real-time high-resolution imaging of the cerebral vasculature. Preterm lambs (0.8 gestation, n = 4) were delivered via caesarean section, anesthetized, and ventilated. SR microangiography of the right cerebral hemisphere was performed with iodine contrast administered into the right carotid artery during PEEP ventilation of 5 and 10 cmH2O. Carotid blood flow was measured using an ultrasonic flow probe placed around the left carotid artery. An increase of PEEP from 5 to 10 cmH2O increased the diameter of small cerebral vessels (<150 µm) but decreased the diameter of larger cerebral vessels (>500 µm) in all four lambs. Additionally, the higher PEEP increased the cerebral contrast transit time in three of the four lambs. Carotid blood flow increased in two lambs, which also had increased carbon dioxide levels during PEEP 10. Our results suggest that PEEP of 10 cmH2O alters the preterm cerebral hemodynamics, with prolonged cerebral blood flow transit and engorgement of small cerebral microvessels likely due to the increased intrathoracic pressure. These microvascular changes are generally not reflected in global assessment of cerebral blood flow or oxygenation.NEW & NOTEWORTHY An increase of positive end-expiratory pressure (PEEP) from 5 to 10 cmH2O increased the diameter of small cerebral vessels (<150 µm) but decreased the diameter of larger cerebral vessels (>500 µm). This suggests increased intrathoracic pressure due to high PEEP can drive microvessel engorgement in the preterm brain, which may play a role in cerebrovascular injury.
Collapse
Affiliation(s)
- Ishmael Miguel Inocencio
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Nhi Thao Tran
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia.,School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
| | - Shinji Nakamura
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Song J Khor
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Manon Wiersma
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Katja Stoecker
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia
| | - Graeme R Polglase
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Centre, Osaka, Japan.,Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Flora Y Wong
- The Ritchie Centre, The Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Paediatrics, Monash University, Melbourne, VIC, Australia.,Monash Newborn, Monash Medical Centre, Melbourne, VIC, Australia
| |
Collapse
|
10
|
Waddingham MT, Sonobe T, Tsuchimochi H, Edgley AJ, Sukumaran V, Chen YC, Hansra SS, Schwenke DO, Umetani K, Aoyama K, Yagi N, Kelly DJ, Gaderi S, Herwig M, Kolijn D, Mügge A, Paulus WJ, Ogo T, Shirai M, Hamdani N, Pearson JT. Diastolic dysfunction is initiated by cardiomyocyte impairment ahead of endothelial dysfunction due to increased oxidative stress and inflammation in an experimental prediabetes model. J Mol Cell Cardiol 2019; 137:119-131. [DOI: 10.1016/j.yjmcc.2019.10.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/10/2019] [Accepted: 10/18/2019] [Indexed: 12/19/2022]
|
11
|
Nagano K, Kwon C, Ishida J, Hashimoto T, Kim JD, Kishikawa N, Murao M, Kimura K, Kasuya Y, Kimura S, Chen YC, Tsuchimochi H, Shirai M, Pearson JT, Fukamizu A. Cooperative action of APJ and α1A-adrenergic receptor in vascular smooth muscle cells induces vasoconstriction. J Biochem 2019; 166:383-392. [DOI: 10.1093/jb/mvz071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 08/29/2019] [Indexed: 12/21/2022] Open
Abstract
Abstract
The apelin receptor (APJ), a receptor for apelin and elabela/apela, induces vasodilation and vasoconstriction in blood vessels. However, the prolonged effects of increased APJ-mediated signalling, involving vasoconstriction, in smooth muscle cells have not been fully characterized. Here, we investigated the vasoactive effects of APJ gain of function under the control of the smooth muscle actin (SMA) gene promoter in mice. Transgenic overexpression of APJ (SMA-APJ) conferred sensitivity to blood pressure and vascular contraction induced by apelin administration in vivo. Interestingly, ex vivo experiments showed that apelin markedly increased the vasoconstriction of isolated aorta induced by noradrenaline (NA), an agonist for α- and β-adrenergic receptors, or phenylephrine, a specific agonist for α1-adrenergic receptor (α1-AR). In addition, intracellular calcium influx was augmented by apelin with NA in HEK293T cells expressing APJ and α1A-AR. To examine the cooperative action of APJ and α1A-AR in the regulation of vasoconstriction, we developed α1A-AR deficient mice using a genome-editing technique, and then established SMA-APJ/α1A-AR-KO mice. In the latter mouse line, aortic vasoconstriction induced by a specific agonist for α1A-AR, A-61603, were significantly less than in SMA-APJ mice. These results suggest that the APJ-enhanced response requires α1A-AR to contract vessels coordinately.
Collapse
Affiliation(s)
- Katsumasa Nagano
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Chulwon Kwon
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Junji Ishida
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Tatsuo Hashimoto
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
- Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Japan
| | - Jun-Dal Kim
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Nana Kishikawa
- College of Agro-biological Resource Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Mei Murao
- Division of Nephrology and Hypertension, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Japan
| | - Kenjiro Kimura
- Tokyo Takanawa Hospital, 3-10-11 Takanawa, Minato-ku, Tokyo, Japan
| | - Yoshitoshi Kasuya
- Department of Biochemistry and Molecular Pharmacology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, Japan
| | - Sadao Kimura
- Department of Biochemistry and Molecular Pharmacology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, Japan
| | - Yi-Ching Chen
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Australia
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita-shi, Osaka, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita-shi, Osaka, Japan
| | - James T Pearson
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Australia
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita-shi, Osaka, Japan
| | - Akiyoshi Fukamizu
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
- The World Premier International Research Center Initiative (WPI), International Institute for Integrative Sleep Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| |
Collapse
|
12
|
Cao Y, Zhang M, Ding H, Chen Z, Tang B, Wu T, Xiao B, Duan C, Ni S, Jiang L, Luo Z, Li C, Zhao J, Liao S, Yin X, Fu Y, Xiao T, Lu H, Hu J. Synchrotron radiation micro-tomography for high-resolution neurovascular network morphology investigation. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:607-618. [PMID: 31074423 DOI: 10.1107/s1600577519003060] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 02/27/2019] [Indexed: 06/09/2023]
Abstract
There has been increasing interest in using high-resolution micro-tomography to investigate the morphology of neurovascular networks in the central nervous system, which remain difficult to characterize due to their microscopic size as well as their delicate and complex 3D structure. Synchrotron radiation X-ray imaging, which has emerged as a cutting-edge imaging technology with a high spatial resolution, provides a novel platform for the non-destructive imaging of microvasculature networks at a sub-micrometre scale. When coupled with computed tomography, this technique allows the characterization of the 3D morphology of vasculature. The current review focuses on recent progress in developing synchrotron radiation methodology and its application in probing neurovascular networks, especially the pathological changes associated with vascular abnormalities in various model systems. Furthermore, this tool represents a powerful imaging modality that improves our understanding of the complex biological interactions between vascular function and neuronal activity in both physiological and pathological states.
Collapse
Affiliation(s)
- Yong Cao
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Mengqi Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Hui Ding
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Zhuohui Chen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Bin Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Tianding Wu
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Chunyue Duan
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Shuangfei Ni
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Liyuan Jiang
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Zixiang Luo
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Chengjun Li
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Jinyun Zhao
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Shenghui Liao
- School of Information Science and Engineering, Central South University, Changsha 410008, People's Republic of China
| | - Xianzhen Yin
- Center for Drug Delivery System, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 20203, People's Republic of China
| | - Yalan Fu
- Shanghai Synchrotron Radiation Facility/Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 21204, People's Republic of China
| | - Tiqiao Xiao
- Shanghai Synchrotron Radiation Facility/Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 21204, People's Republic of China
| | - Hongbin Lu
- Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, Hunan 410008, People's Republic of China
| | - Jianzhong Hu
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| |
Collapse
|
13
|
Sukumaran V, Tsuchimochi H, Sonobe T, Shirai M, Pearson JT. Liraglutide Improves Renal Endothelial Function in Obese Zucker Rats on a High-Salt Diet. J Pharmacol Exp Ther 2019; 369:375-388. [DOI: 10.1124/jpet.118.254821] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 03/21/2019] [Indexed: 01/11/2023] Open
|
14
|
Gu S, Xue J, Xi Y, Tang R, Jin W, Chen JJ, Zhang X, Shao ZM, Wu J. Evaluating the effect of Avastin on breast cancer angiogenesis using synchrotron radiation. Quant Imaging Med Surg 2019; 9:418-426. [PMID: 31032189 DOI: 10.21037/qims.2019.03.09] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background The visualization of microvasculature is an essential step in understanding the mechanisms underlying early vessel disorders involved in breast cancer and for developing effective therapeutic strategies. However, generating detailed and reproducible data using immunohistochemistry analysis of breast cancer angiogenesis has been difficult. Methods To analyze the diversification of angiogenesis in the development of tumor growth and evaluate the anti-vascular effects of Avastin (bevacizumab), we used new X-ray microangiography and third-generation synchrotron radiation-based micro-computed tomography (SR micro-CT) technology. With these techniques, we were able to investigate the structures and density of microvessels in xenograft mouse models (n=24). Barium sulfate nanoparticles were injected into the left cardiac ventricle of the mice to allow the visualization of blood vessels. Results Three-dimensional structures of microvessels were displayed with a high spatial image resolution of 20-30 µm. The density of angiogenesis and the incidence of lung metastasis were significantly reduced in xenograft mouse models of breast cancer treated with Avastin compared with control groups. Also, the density of smaller vessels (diameter <50 µm) was significantly decreased in the Avastin-treated mice, while the density of larger vessels (diameter >100 µm) was not significantly changed. Conclusions Avastin inhibited tumor growth and lung metastasis by reducing microvessels. Additionally, synchrotron radiation (SR) techniques are useful as an additional tool for more precise quantification of angiogenesis.
Collapse
Affiliation(s)
- Shengmei Gu
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jingyan Xue
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Yan Xi
- School of Biomedical Engineering, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Rongbiao Tang
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, China
| | - Wei Jin
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jia-Jian Chen
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xi Zhang
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhi-Min Shao
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Jiong Wu
- Department of Breast Surgery, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.,Collaborative Innovation Center for Cancer Medicine, Shanghai 200032, China
| |
Collapse
|
15
|
Luo Y, Yin X, Shi S, Ren X, Zhang H, Wang Z, Cao Y, Tang M, Xiao B, Zhang M. Non-destructive 3D Microtomography of Cerebral Angioarchitecture Changes Following Ischemic Stroke in Rats Using Synchrotron Radiation. Front Neuroanat 2019; 13:5. [PMID: 30766481 PMCID: PMC6365468 DOI: 10.3389/fnana.2019.00005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 01/15/2019] [Indexed: 01/29/2023] Open
Abstract
A better understanding of functional changes in the cerebral microvasculature following ischemic injury is essential to elucidate the pathogenesis of stroke. Up to now, the simultaneous depiction and stereological analysis of 3D micro-architectural changes of brain vasculature with network disorders remains a technical challenge. We aimed to explore the three dimensional (3D) microstructural changes of microvasculature in the rat brain on 4, 6 hours, 3 and 18 days post-ischemia using synchrotron radiation micro-computed tomography (SRμCT) with a per pixel size of 5.2 μm. The plasticity of angioarchitecture was distinctly visualized. Quantitative assessments of time-related trends after focal ischemia, including number of branches, number of nodes, and frequency distribution of vessel diameter, reached a peak at 6 h and significantly decreased at 3 days and initiated to form cavities. The detected pathological changes were also proven by histological tests. We depicted a novel methodology for the 3D analysis of vascular repair in ischemic injury, both qualitatively and quantitatively. Cerebral angioarchitecture sustained 3D remodeling and modification during the healing process. The results might provide a deeper insight into the compensatory mechanisms of microvasculature after injury, suggesting that SRμCT is able to provide a potential new platform for deepening imaging pathological changes in complicated angioarchitecture and evaluating potential therapeutic targets for stroke.
Collapse
Affiliation(s)
- Yonghong Luo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Xianzhen Yin
- Center for Drug Delivery System, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Shupeng Shi
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaolei Ren
- Department of Orthopaedics, Second Xiangya Hospital, Central South University, Changsha, China
| | - Haoran Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhuolu Wang
- Department of Breast Surgery, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China.,Department of General Surgery, Xiangya Hospital, Central South University, Changsha, China
| | - Yong Cao
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, China
| | - Mimi Tang
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China.,Institute of Hospital Pharmacy, Xiangya Hospital, Central South University, Changsha, China
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Mengqi Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| |
Collapse
|
16
|
Katare R, Pearson JT, Lew JKS, Wei M, Tsuchimouchi H, Du CK, Zhan DY, Umetani K, Shirai M, Schwenke DO. Progressive Decrease in Coronary Vascular Function Associated With Type 2 Diabetic Heart Disease. Front Physiol 2018; 9:696. [PMID: 29928236 PMCID: PMC5997806 DOI: 10.3389/fphys.2018.00696] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/18/2018] [Indexed: 12/18/2022] Open
Abstract
Background: The causal factors underpinning the onset and progression of diabetic heart disease (DHD) remain to be fully elucidated. Myocardial function is critically dependent on optimal coronary blood flow. Considering vascular disease occurs early in diabetes due to endothelial dysfunction, this study aimed to determine whether impaired coronary perfusion contributes to the origins of myocardial dysfunction in DHD, or whether coronary and cardiac dysfunction are independent pathologies associated with diabetes. Methods: Synchrotron radiation microangiography was used to image the coronary circulation of type-2 diabetic db/db and non-diabetic db/+ mice in vivo at 8, 16, and 24 weeks of age. We further assessed vascular function based on the vasodilatory responses to acetylcholine (ACh, 3 μg/kg/min), sodium nitroprusside (SNP, 5 μg/kg/min) and the Rho-kinase inhibitor, fasudil (20 mg/kg, i.v.). Cardiac function was assessed using echocardiography, and cardiac eNOS and ROCK expression were measured using immunohistochemistry. Results: Coronary and cardiac function were normal in 8-week-old diabetic mice. However, by 16 weeks of age, diabetic mice had advanced cardiac dysfunction. In comparison, normal coronary perfusion was preserved in diabetes until 24 weeks of age. Moreover, only the 24-week-old diabetic mice showed clear evidence of advanced coronary vascular dysfunction, based on (i) the absence of a vasodilatory response to ACh, and (ii) an exaggerated vasodilatory response to fasudil. Interestingly, fasudil also restored normal coronary perfusion in the 24-week-old diabetic heart by restoring blood flow to previously constricted vessels (diameter < 100 μm). Importantly, there was a ubiquitous decrease, and increase, in the cardiac expression of eNOS and ROCK, respectively. Conclusion: These results suggest that both cardiac and coronary dysfunction appear to have independent origins associated with diabetes and Rho-kinase pathway may be playing a role in the onset and progression of DHD.
Collapse
Affiliation(s)
- Rajesh Katare
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan.,Bioscience Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Jason Kar-Sheng Lew
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Melanie Wei
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Hirotsugu Tsuchimouchi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Cheng-Kun Du
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Dong-Yun Zhan
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Hyōgo, Japan
| | - Mikiyasu Shirai
- Department of Advanced Medical Research for Pulmonary Hypertension, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Daryl O Schwenke
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| |
Collapse
|
17
|
Pearson JT, Yoshimoto M, Chen YC, Sultani R, Edgley AJ, Nakaoka H, Nishida M, Umetani K, Waddingham MT, Jin HL, Zhang Y, Kelly DJ, Schwenke DO, Inagaki T, Tsuchimochi H, Komuro I, Yamashita S, Shirai M. Widespread Coronary Dysfunction in the Absence of HDL Receptor SR-B1 in an Ischemic Cardiomyopathy Mouse Model. Sci Rep 2017; 7:18108. [PMID: 29273789 PMCID: PMC5741771 DOI: 10.1038/s41598-017-18485-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 12/12/2017] [Indexed: 02/02/2023] Open
Abstract
Reduced clearance of lipoproteins by HDL scavenger receptor class B1 (SR-B1) plays an important role in occlusive coronary artery disease. However, it is not clear how much microvascular dysfunction contributes to ischemic cardiomyopathy. Our aim was to determine the distribution of vascular dysfunction in vivo in the coronary circulation of male mice after brief exposure to Paigen high fat diet, and whether this vasomotor dysfunction involved nitric oxide (NO) and or endothelium derived hyperpolarization factors (EDHF). We utilised mice with hypomorphic ApoE lipoprotein that lacked SR-B1 (SR-B1−/−/ApoER61h/h, n = 8) or were heterozygous for SR-B1 (SR-B1+/−/ApoER61h/h, n = 8) to investigate coronary dilator function with synchrotron microangiography. Partially occlusive stenoses were observed in vivo in SR-B1 deficient mice only. Increases in artery-arteriole calibre to acetylcholine and sodium nitroprusside stimulation were absent in SR-B1 deficient mice. Residual dilation to acetylcholine following L-NAME (50 mg/kg) and sodium meclofenamate (3 mg/kg) blockade was present in both mouse groups, except at occlusions, indicating that EDHF was not impaired. We show that SR-B1 deficiency caused impairment of NO-mediated dilation of conductance and microvessels. Our findings also suggest EDHF and prostanoids are important for global perfusion, but ultimately the loss of NO-mediated vasodilation contributes to atherothrombotic progression in ischemic cardiomyopathy.
Collapse
Affiliation(s)
- James T Pearson
- Monash Biomedical Imaging Facility, Melbourne, Victoria, Australia. .,Department of Physiology, Monash University, Melbourne, Victoria, Australia. .,Australian Synchrotron, Melbourne, Victoria, Australia. .,National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
| | - Misa Yoshimoto
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.,Department of Health Sciences, Nara Women's University, Nara, Japan
| | - Yi Ching Chen
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Rohullah Sultani
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Amanda J Edgley
- Department of Physiology, Monash University, Melbourne, Victoria, Australia.,St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Hajime Nakaoka
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Makoto Nishida
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Hyogo, Japan
| | - Mark T Waddingham
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Hui-Ling Jin
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - Yuan Zhang
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Darren J Kelly
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Daryl O Schwenke
- Department of Physiology - HeartOtago, University of Otago, Dunedin, New Zealand
| | - Tadakatsu Inagaki
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | | | - Issei Komuro
- Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Shizuya Yamashita
- Departments of Community Medicine and Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.,Rinku General Medical Center, Izumisano, Osaka, Japan
| | - Mikiyasu Shirai
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| |
Collapse
|
18
|
Nicolas JD, Bernhardt M, Markus A, Alves F, Burghammer M, Salditt T. Scanning X-ray diffraction on cardiac tissue: automatized data analysis and processing. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:1163-1172. [PMID: 29091059 DOI: 10.1107/s1600577517011936] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 08/16/2017] [Indexed: 05/20/2023]
Abstract
A scanning X-ray diffraction study of cardiac tissue has been performed, covering the entire cross section of a mouse heart slice. To this end, moderate focusing by compound refractive lenses to micrometer spot size, continuous scanning, data acquisition by a fast single-photon-counting pixel detector, and fully automated analysis scripts have been combined. It was shown that a surprising amount of structural data can be harvested from such a scan, evaluating the local scattering intensity, interfilament spacing of the muscle tissue, the filament orientation, and the degree of anisotropy. The workflow of data analysis is described and a data analysis toolbox with example data for general use is provided. Since many cardiomyopathies rely on the structural integrity of the sarcomere, the contractile unit of cardiac muscle cells, the present study can be easily extended to characterize tissue from a diseased heart.
Collapse
Affiliation(s)
- Jan David Nicolas
- Institut für Röntgenphysik, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Marten Bernhardt
- Institut für Röntgenphysik, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - Andrea Markus
- Max-Planck-Institut für Experimentelle Medizin, Hermann-Rein-Straße 3, 37075 Göttingen, Germany
| | - Frauke Alves
- Max-Planck-Institut für Experimentelle Medizin, Hermann-Rein-Straße 3, 37075 Göttingen, Germany
| | - Manfred Burghammer
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Tim Salditt
- Institut für Röntgenphysik, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| |
Collapse
|
19
|
Torii M, Fukui T, Inoue M, Kanao S, Umetani K, Shirai M, Inagaki T, Tsuchimochi H, Pearson JT, Toi M. Analysis of the microvascular morphology and hemodynamics of breast cancer in mice using SPring-8 synchrotron radiation microangiography. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:1039-1047. [PMID: 28862627 PMCID: PMC5580789 DOI: 10.1107/s1600577517008372] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 06/06/2017] [Indexed: 05/13/2023]
Abstract
Tumor vasculature is characterized by morphological and functional abnormalities. However, analysis of the dynamics in blood flow is still challenging because of limited spatial and temporal resolution. Synchrotron radiation (SR) microangiography above the K-edge of the iodine contrast agent can provide high-contrast imaging of microvessels in time orders of milliseconds. In this study, mice bearing the human breast cancer cell lines MDAMB231 and NOTCH4 overexpression in MDAMB231 (MDAMB231NOTCH4+) and normal mice were assessed using SR microangiography. NOTCH is transmembrane protein that has crucial roles for vasculogenesis, angiogenesis and tumorigenesis, and NOTCH4 is considered to be a cause of high-flow arteriovenous shunting. A subgroup of mice received intravenous eribulin treatment, which is known to improve intratumor core circulation (MDAMB231_eribulin). Microvessel branches from approximately 200 µm to less than 20 µm in diameter were observed within the same visual field. The mean transition time (MTT) was measured as a dynamic parameter and quantitative analysis was performed. MTT in MDAMB231 was longer than that in normal tissue, and MDAMB231NOTCH4+ showed shorter MTT [5.0 ± 1.4 s, 3.6 ± 1.0 s and 3.6 ± 1.1 s (mean ± standard deviation), respectively]. After treatment, average MTT was correlated to tumor volume (r = 0.999) in MDAMB231_eribulin, while in contrast there was no correlation in MDAMB231 (r = -0.026). These changes in MTT profile are considered to be driven by the modulation of intratumoral circulation dynamics. These results demonstrate that a SR microangiography approach enables quantitative analysis of morphological and dynamic characteristics of tumor vasculature in vivo. Further studies will reveal new findings concerning vessel function in tumors.
Collapse
Affiliation(s)
- Masae Torii
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Toshifumi Fukui
- Medical Imaging System Development Center, Canon, Tokyo, Japan
| | - Masashi Inoue
- Medical Imaging System Development Center, Canon, Tokyo, Japan
| | - Shotaro Kanao
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Keiji Umetani
- Research and Utilization Division, Japan Synchrotron Radiation Research Institute, Hyogo, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Tadakatsu Inagaki
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - James T. Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Masakazu Toi
- Department of Breast Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| |
Collapse
|
20
|
Miya K, Matsushita S, Hyodo K, Tokunaga C, Sakamoto H, Mizutani T, Hiramatsu Y. Renal contrast microangiography with synchrotron radiation: a novel method for visualizing structures within nephrons in vivo. Acta Radiol 2017; 58:505-510. [PMID: 27439400 DOI: 10.1177/0284185116658685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background No non-invasive method of observing renal microcirculation in vivo has been established as yet. Although angiography is considered to be ideally suited for the purpose, conventional X-rays cannot be used to image structures smaller than 100 µm. Purpose To develop a method for visualizing the renal arterioles, glomeruli, and proximal tubules of rats in vivo making use of synchrotron radiation. Material and Methods Male Wistar rats were anesthetized, and a catheter was inserted via laparotomy into the abdominal aorta with its tip placed above the renal arteries. The rats were paralyzed with a neuromuscular blocking agent and mechanically ventilated. An inorganic iodine contrast medium was injected via the catheter. The SR derived X-rays transmitted through the subjects were recorded with a CCD camera. Two-dimensional images with a pixel size of 9 µm were obtained. The exposure time was fixed at 50 ms, with a maximum acquisition rate of three images/s. Results Renal arterioles as small as 18 µm in diameter, glomeruli with an average diameter of 173 ± 21 µm, as well as proximal tubules, were clearly visualized. In addition, glomerular density at the peripheral renal cortex was measurable. Conclusion Rat renal microcirculation could be successfully observed in real-time, without exteriorization of the kidney in this study.
Collapse
Affiliation(s)
- Ken Miya
- Emergency and Critical Care Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | | | - Kazuyuki Hyodo
- Photon Factory, High Energy Accelerator Research Organization, Tsukuba, Ibaraki, Japan
| | - Chiho Tokunaga
- Cardiovascular Surgery, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hiroaki Sakamoto
- Cardiovascular Surgery, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Taro Mizutani
- Emergency and Critical Care Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yuji Hiramatsu
- Cardiovascular Surgery, University of Tsukuba, Tsukuba, Ibaraki, Japan
| |
Collapse
|
21
|
Hu J, Li P, Yin X, Wu T, Cao Y, Yang Z, Jiang L, Hu S, Lu H. Nondestructive imaging of the internal microstructure of vessels and nerve fibers in rat spinal cord using phase-contrast synchrotron radiation microtomography. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:482-489. [PMID: 28244444 DOI: 10.1107/s1600577517000121] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 01/04/2017] [Indexed: 06/06/2023]
Abstract
The spinal cord is the primary neurological link between the brain and other parts of the body, but unlike those of the brain, advances in spinal cord imaging have been challenged by the more complicated and inhomogeneous anatomy of the spine. Fortunately with the advancement of high technology, phase-contrast synchrotron radiation microtomography has become widespread in scientific research because of its ability to generate high-quality and high-resolution images. In this study, this method has been employed for nondestructive imaging of the internal microstructure of rat spinal cord. Furthermore, digital virtual slices based on phase-contrast synchrotron radiation were compared with conventional histological sections. The three-dimensional internal microstructure of the intramedullary arteries and nerve fibers was vividly detected within the same spinal cord specimen without the application of a stain or contrast agent or sectioning. With the aid of image post-processing, an optimization of vessel and nerve fiber images was obtained. The findings indicated that phase-contrast synchrotron radiation microtomography is unique in the field of three-dimensional imaging and sets novel standards for pathophysiological investigations in various neurovascular diseases.
Collapse
Affiliation(s)
- Jianzhong Hu
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Ping Li
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Xianzhen Yin
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 200135, People's Republic of China
| | - Tianding Wu
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Yong Cao
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Zhiming Yang
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Liyuan Jiang
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Shiping Hu
- Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| | - Hongbin Lu
- Department of Sports Medicine, Research Centre of Sports Medicine, Xiangya Hospital, Central South University, Changsha 410008, People's Republic of China
| |
Collapse
|
22
|
Lu Y, Tang G, Lin H, Lin X, Jiang L, Yang GY, Wang Y. A biosafety evaluation of synchrotron radiation X-ray to skin and bone marrow: single dose irradiation study of rats and macaques. Int J Radiat Biol 2017; 93:637-645. [PMID: 28112006 DOI: 10.1080/09553002.2017.1286049] [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: 10/20/2022]
Abstract
PURPOSE Very limited experimental data is available regarding the safe dosages related to synchrotron radiation (SR) procedures. We used young rats and macaques to address bone marrow and skin tolerance to various doses of synchrotron radiation. METHODS Rats were subjected to 0, 0.5, 2.5, 5, 25 or 100 Gy local SR X-ray irradiation at left hind limb. Rat blood samples were analyzed at 2-90 days after irradiation. The SR X-ray irradiated skin and tibia were sectioned for morphological examination. For non-human primate study, three male macaques were subjected to 0.5 or 2.5 Gy SR X-ray on crus. Skin responses of macaques were observed. RESULTS All rats that received SR X-ray irradiation doses greater than 2.5 Gy experienced hair loss and bone-growth inhibition, which were accompanied by decreased number of follicles, thickened epidermal layer, and decreased density of bone marrow cells (p < 0.05). Macaque skin could tolerate 0.5 Gy SR X-ray but showed significant hair loss when the dose was raised above 2.5 Gy. CONCLUSION The safety threshold doses of SR X-ray for rat skin, bone marrow and macaque skin are between 0.5 and 2.5 Gy. Our study provided essential information regarding the biosafety of SR X-ray irradiation.
Collapse
Affiliation(s)
- Yifan Lu
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China
| | - Guanghui Tang
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China
| | - Hui Lin
- b School of Electronic Science and Application Physics , Hefei University of Technology , Hefei , Anhui , China
| | - Xiaojie Lin
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China
| | - Lu Jiang
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China
| | - Guo-Yuan Yang
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China.,c Department of Neurology, Ruijin Hospital, School of Medicine , Shanghai Jiao Tong University , Shanghai , China
| | - Yongting Wang
- a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China
| |
Collapse
|
23
|
Cao Y, Zhou Y, Ni S, Wu T, Li P, Liao S, Hu J, Lu H. Three Dimensional Quantification of Microarchitecture and Vessel Regeneration by Synchrotron Radiation Microcomputed Tomography in a Rat Model of Spinal Cord Injury. J Neurotrauma 2016; 34:1187-1199. [PMID: 27676128 DOI: 10.1089/neu.2016.4697] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
A full understanding of the mechanisms behind spinal cord injury (SCI) processes requires reliable three-dimensional (3D) imaging tools for a thorough analysis of changes in angiospatial architecture. We aimed to use synchrotron radiation μCT (SRμCT) to characterize 3D temporal-spatial changes in microvasculature post-SCI. Morphometrical measurements revealed a significant decrease in vascular volume fraction, vascular bifurcation density, vascular segment density, and vascular connectivity density 1 day post-injury, followed by a gradual increase at 3, 7, and 14 days. At 1 day post-injury, SRμCT revealed an increase in vascular tortuosity (VT), which reached a plateau after 7 days and decreased slightly during the healing process. In addition, SRμCT images showed that vessels were largely concentrated in the gray matter 1 day post-injury. The maximal endothelial cell proliferation rate was detected at 7 days post-injury. The 3D morphology of the cavity appears in the spinal cord at 28 days post-injury. We describe a methodology for 3D analysis of vascular repair in SCI and reveal that endogenous revascularization occurs during the healing process. The spinal cord microvasculature configuration undergoes 3D remodeling and modification during the post-injury repair process. Examination of these processes might contribute to a full understanding of the compensatory vascular mechanisms after injury and aid in the development of novel and effective treatment for SCI.
Collapse
Affiliation(s)
- Yong Cao
- 1 Department of Spine Surgery, Central South University , Changsha, China
| | - Yuan Zhou
- 2 Department of Thoracic Surgery, Xiangya Hospital, Central South University , Changsha, China
| | - Shuangfei Ni
- 1 Department of Spine Surgery, Central South University , Changsha, China
| | - Tianding Wu
- 1 Department of Spine Surgery, Central South University , Changsha, China
| | - Ping Li
- 1 Department of Spine Surgery, Central South University , Changsha, China
| | - Shenghui Liao
- 3 School of Information Science and Engineering, Central South University , Changsha, Changsha, China
| | - Jianzhong Hu
- 1 Department of Spine Surgery, Central South University , Changsha, China
| | - Hongbin Lu
- 4 Department of Sports Medicine, Research Centre of Sports Medicine, Xiangya Hospital, Central South University , Changsha, China
| |
Collapse
|
24
|
Kobirumaki-Shimozawa F, Oyama K, Shimozawa T, Mizuno A, Ohki T, Terui T, Minamisawa S, Ishiwata S, Fukuda N. Nano-imaging of the beating mouse heart in vivo: Importance of sarcomere dynamics, as opposed to sarcomere length per se, in the regulation of cardiac function. ACTA ACUST UNITED AC 2016; 147:53-62. [PMID: 26712849 PMCID: PMC4692490 DOI: 10.1085/jgp.201511484] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
¡Vive la différence! In cardiac contraction, the reduction in sarcomere length—rather than length itself—determines contractile force. Sarcomeric contraction in cardiomyocytes serves as the basis for the heart’s pump functions in mammals. Although it plays a critical role in the circulatory system, myocardial sarcomere length (SL) change has not been directly measured in vivo under physiological conditions because of technical difficulties. In this study, we developed a high speed (100–frames per second), high resolution (20-nm) imaging system for myocardial sarcomeres in living mice. Using this system, we conducted three-dimensional analysis of sarcomere dynamics in left ventricular myocytes during the cardiac cycle, simultaneously with electrocardiogram and left ventricular pressure measurements. We found that (a) the working range of SL was on the shorter end of the resting distribution, and (b) the left ventricular–developed pressure was positively correlated with the SL change between diastole and systole. The present findings provide the first direct evidence for the tight coupling of sarcomere dynamics and ventricular pump functions in the physiology of the heart.
Collapse
Affiliation(s)
- Fuyu Kobirumaki-Shimozawa
- Department of Cell Physiology and Department of Anesthesiology, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan
| | - Kotaro Oyama
- Department of Cell Physiology and Department of Anesthesiology, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan Department of Physics and Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Togo Shimozawa
- Department of Physics and Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Akari Mizuno
- Department of Physics and Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Takashi Ohki
- Department of Physics and Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Takako Terui
- Department of Cell Physiology and Department of Anesthesiology, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan
| | - Susumu Minamisawa
- Department of Cell Physiology and Department of Anesthesiology, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan
| | - Shin'ichi Ishiwata
- Department of Physics and Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan Waseda Bioscience Research Institute in Singapore, Waseda University, Helios, Singapore 138667
| | - Norio Fukuda
- Department of Cell Physiology and Department of Anesthesiology, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan
| |
Collapse
|
25
|
Shimozawa T, Hirokawa E, Kobirumaki-Shimozawa F, Oyama K, Shintani SA, Terui T, Kushida Y, Tsukamoto S, Fujii T, Ishiwata S, Fukuda N. In vivo cardiac nano-imaging: A new technology for high-precision analyses of sarcomere dynamics in the heart. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 124:31-40. [PMID: 27664770 DOI: 10.1016/j.pbiomolbio.2016.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 09/15/2016] [Accepted: 09/20/2016] [Indexed: 12/01/2022]
Abstract
The cardiac pump function is a result of a rise in intracellular Ca2+ and the ensuing sarcomeric contractions [i.e., excitation-contraction (EC) coupling] in myocytes in various locations of the heart. In order to elucidate the heart's mechanical properties under various settings, cardiac imaging is widely performed in today's clinical as well as experimental cardiology by using echocardiogram, magnetic resonance imaging and computed tomography. However, because these common techniques detect local myocardial movements at a spatial resolution of ∼100 μm, our knowledge on the sub-cellular mechanisms of the physiology and pathophysiology of the heart in vivo is limited. This is because (1) EC coupling occurs in the μm partition in a myocyte and (2) cardiac sarcomeres generate active force upon a length change of ∼100 nm on a beat-to-beat basis. Recent advances in optical technologies have enabled measurements of intracellular Ca2+ dynamics and sarcomere length displacements at high spatial and temporal resolution in the beating heart of living rodents. Future studies with these technologies are warranted to open a new era in cardiac research.
Collapse
Affiliation(s)
- Togo Shimozawa
- Department of Life Science and Medical Bioscience, School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Sinjuku-ku, Tokyo 162-8480, Japan
| | - Erisa Hirokawa
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Fuyu Kobirumaki-Shimozawa
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Kotaro Oyama
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Seine A Shintani
- Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takako Terui
- Department of Anesthesiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Yasuharu Kushida
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Seiichi Tsukamoto
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Teruyuki Fujii
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Shin'ichi Ishiwata
- Department of Physics, Faculty of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Norio Fukuda
- Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan.
| |
Collapse
|
26
|
Shirai M, Yagi N, Umetani K. SPring-8 synchrotron radiation imaging for analyzing cardiovascular function in anesthetized small animals. Nihon Yakurigaku Zasshi 2016; 148:92-9. [PMID: 27478048 DOI: 10.1254/fpj.148.92] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
27
|
Chen YC, Inagaki T, Fujii Y, Schwenke DO, Tsuchimochi H, Edgley AJ, Umetani K, Zhang Y, Kelly DJ, Yoshimoto M, Nagai H, Evans RG, Kuwahira I, Shirai M, Pearson JT. Chronic intermittent hypoxia accelerates coronary microcirculatory dysfunction in insulin-resistant Goto-Kakizaki rats. Am J Physiol Regul Integr Comp Physiol 2016; 311:R426-39. [DOI: 10.1152/ajpregu.00112.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/30/2016] [Indexed: 12/20/2022]
Abstract
Chronic intermittent hypoxia (IH) induces oxidative stress and inflammation, which impair vascular endothelial function. Long-term insulin resistance also leads to endothelial dysfunction. We determined, in vivo, whether the effects of chronic IH and insulin resistance on endothelial function augment each other. Male 12-wk-old Goto-Kakizaki (GK) and Wistar control rats were subjected to normoxia or chronic IH (90-s N2, 5% O2 at nadir, 90-s air, 20 cycles/h, 8 h/day) for 4 wk. Coronary endothelial function was assessed using microangiography with synchrotron radiation. Imaging was performed at baseline, during infusion of acetylcholine (ACh, 5 μg·kg−1·min−1) and then sodium nitroprusside (SNP, 5 μg·kg−1·min−1), after blockade of both nitric oxide (NO) synthase (NOS) with Nω-nitro-l-arginine methyl ester (l-NAME, 50 mg/kg) and cyclooxygenase (COX, meclofenamate, 3 mg/kg), and during subsequent ACh. In GK rats, coronary vasodilatation in response to ACh and SNP was blunted compared with Wistar rats, and responses to ACh were abolished after blockade. In Wistar rats, IH blunted the ability of ACh or SNP to increase the number of visible vessels. In GK rats exposed to IH, neither ACh nor SNP were able to increase visible vessel number or caliber, and blockade resulted in marked vasoconstriction. Our findings indicate that IH augments the deleterious effects of insulin resistance on coronary endothelial function. They appear to increase the dependence of the coronary microcirculation on NO and/or vasodilator prostanoids, and greatly blunt the residual vasodilation in response to ACh after blockade of NOS/COX, presumably mediated by endothelium-derived hyperpolarizing factors.
Collapse
Affiliation(s)
- Yi Ching Chen
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Tadakatsu Inagaki
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Yutaka Fujii
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Daryl O. Schwenke
- Department of Physiology-Heart Otago, University of Otago, Dunedin, New Zealand
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Amanda J. Edgley
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Yuan Zhang
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Darren J. Kelly
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Misa Yoshimoto
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Hisashi Nagai
- Departments of Clinical Laboratory Medicine and Forensic Medicine, University of Tokyo, Tokyo, Japan
| | - Roger G. Evans
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Ichiro Kuwahira
- Department of Pulmonary Medicine, Tokai University Tokyo Hospital, Tokai University, Tokyo, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - James T. Pearson
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
- Monash Biomedical Imaging Facility, Melbourne, Australia; and
- Australian Synchrotron, Melbourne, Australia
| |
Collapse
|
28
|
Diong C, Jones PP, Tsuchimochi H, Gray EA, Hughes G, Inagaki T, Bussey CT, Fujii Y, Umetani K, Shirai M, Schwenke DO. Sympathetic hyper-excitation in obesity and pulmonary hypertension: physiological relevance to the 'obesity paradox'. Int J Obes (Lond) 2016; 40:938-46. [PMID: 27001546 DOI: 10.1038/ijo.2016.33] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/10/2016] [Accepted: 01/28/2016] [Indexed: 02/07/2023]
Abstract
BACKGROUND Within the lung, sympathetic nerve activity (SNA) has an important role in facilitating pulmonary vasodilation. As SNA is elevated in obesity, we aimed to assess the impact of sympathetic hyper-excitation on pulmonary vascular homeostasis in obesity, and its potential role in ameliorating the severity of pulmonary hypertension (PH); the well-documented 'obesity paradox' phenomenon. METHODS Zucker obese and lean rats were exposed to normoxia or chronic hypoxia (CH-10% O2) for 2 weeks. Subsequently, pulmonary SNA (pSNA) was recorded (electrophysiology), or the pulmonary microcirculation was visualized using Synchrotron microangiography. Acute hypoxic pulmonary vasoconstriction (HPV) was assessed before and after blockade of β1-adrenergic receptors (ARs) (atenolol, 3 mg kg(-1)) and β1+β2-adrenergic (propranolol, 2 mg kg(-1)). RESULTS pSNA of normoxic obese rats was higher than lean counterparts (2.4 and 0.5 μV s, respectively). SNA was enhanced following the development of PH in lean rats, but more so in obese rats (1.7 and 6.8 μV s, respectively). The magnitude of HPV was similar for all groups (for example, ~20% constriction of the 200-300 μm vessels). Although β-blockade did not modify HPV in lean rats, it significantly augmented the HPV in normoxic obese rats (β1 and β2 blockade), and more so in obese rats with PH (β2-blockade alone). Western blots showed, while the expression of pulmonary β1-ARs was similar for all rats, the expression of β2-ARs was downregulated in obesity and PH. CONCLUSIONS This study suggests that sympathetic hyper-excitation in obesity may have an important role in constraining the severity of PH and, thus, contribute in part to the 'obesity paradox' in PH.
Collapse
Affiliation(s)
- C Diong
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| | - P P Jones
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| | - H Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - E A Gray
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| | - G Hughes
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| | - T Inagaki
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - C T Bussey
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| | - Y Fujii
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - K Umetani
- Japan Synchrotron Radiation Research Institute, Hyogo, Japan
| | - M Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - D O Schwenke
- Department of Physiology-HeartOtago, University of Otago, Dunedin, New Zealand
| |
Collapse
|
29
|
Katare R, Rawal S, Munasinghe PE, Tsuchimochi H, Inagaki T, Fujii Y, Dixit P, Umetani K, Kangawa K, Shirai M, Schwenke DO. Ghrelin Promotes Functional Angiogenesis in a Mouse Model of Critical Limb Ischemia Through Activation of Proangiogenic MicroRNAs. Endocrinology 2016; 157:432-45. [PMID: 26672806 DOI: 10.1210/en.2015-1799] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Current therapeutic strategies for the treatment of critical limb ischemia (CLI) have only limited success. Recent in vitro evidence in the literature, using cell lines, proposes that the peptide hormone ghrelin may have angiogenic properties. In this study, we aim to investigate if ghrelin could promote postischemic angiogenesis in a mouse model of CLI and, further, identify the mechanistic pathway(s) that underpin ghrelin's proangiogenic properties. CLI was induced in male CD1 mice by femoral artery ligation. Animals were then randomized to receive either vehicle or acylated ghrelin (150 μg/kg sc) for 14 consecutive days. Subsequently, synchrotron radiation microangiography was used to assess hindlimb perfusion. Subsequent tissue samples were collected for molecular and histological analysis. Ghrelin treatment markedly improved limb perfusion by promoting the generation of new capillaries and arterioles (internal diameter less than 50 μm) within the ischemic hindlimb that were both structurally and functionally normal; evident by robust endothelium-dependent vasodilatory responses to acetylcholine. Molecular analysis revealed that ghrelin's angiogenic properties were linked to activation of prosurvival Akt/vascular endothelial growth factor/Bcl-2 signaling cascade, thus reducing the apoptotic cell death and subsequent fibrosis. Further, ghrelin treatment activated proangiogenic (miR-126 and miR-132) and antifibrotic (miR-30a) microRNAs (miRs) while inhibiting antiangiogenic (miR-92a and miR-206) miRs. Importantly, in vitro knockdown of key proangiogenic miRs (miR-126 and miR-132) inhibited the angiogenic potential of ghrelin. These results therefore suggest that clinical use of ghrelin for the early treatment of CLI may be a promising and potent inducer of reparative vascularization through modulation of key molecular factors.
Collapse
Affiliation(s)
- Rajesh Katare
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Shruti Rawal
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Pujika Emani Munasinghe
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Hirotsugu Tsuchimochi
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Tadakatsu Inagaki
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Yutaka Fujii
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Parul Dixit
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Keiji Umetani
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Kenji Kangawa
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Mikiyasu Shirai
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| | - Daryl O Schwenke
- Department of Physiology, HeartOtago (R.K., S.R., P.E.M., P.D., D.O.S.), University of Otago, Dunedin, 9010 New Zealand; Department of Cardiac Physiology (H.T., T.I., Y.F., M.S.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan; Japan Synchrotron Radiation Research Institute (K.U.), Hyogo, 679-5198 Japan; and Director (K.K.), National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 565-8565 Japan
| |
Collapse
|
30
|
Ultra-high-resolution 3D digitalized imaging of the cerebral angioarchitecture in rats using synchrotron radiation. Sci Rep 2015; 5:14982. [PMID: 26443231 PMCID: PMC4595735 DOI: 10.1038/srep14982] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 09/15/2015] [Indexed: 02/07/2023] Open
Abstract
The angioarchitecture is a fundamental aspect of brain development and physiology. However, available imaging tools are unsuited for non-destructive cerebral mapping of the functionally important three-dimensional (3D) vascular microstructures. To address this issue, we developed an ultra-high resolution 3D digitalized angioarchitectural map for rat brain, based on synchrotron radiation phase contrast imaging (SR-PCI) with pixel size of 5.92 μm. This approach provides a systematic and detailed view of the cerebrovascular anatomy at the micrometer level without any need for contrast agents. From qualitative and quantitative perspectives, the present 3D data provide a considerable insight into the spatial vascular network for whole rodent brain, particularly for functionally important regions of interest, such as the hippocampus, pre-frontal cerebral cortex and the corpus striatum. We extended these results to synchrotron-based virtual micro-endoscopy, thus revealing the trajectory of targeted vessels in 3D. The SR-PCI method for systematic visualization of cerebral microvasculature holds considerable promise for wider application in life sciences, including 3D micro-imaging in experimental models of neurodevelopmental and vascular disorders.
Collapse
|
31
|
Sakamoto H, Matsushita S, Hyodo K, Tokunaga C, Sato F, Hiramatsu Y. A new technique of in vivo synchrotron radiation coronary microangiography in the rat. Acta Radiol 2015; 56:1105-7. [PMID: 25260415 DOI: 10.1177/0284185114549570] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 07/15/2014] [Indexed: 11/15/2022]
Abstract
BACKGROUND Previously, in our laboratory, synchrotron radiation coronary microangiography (SRCA) using Langendorff-perfused rat hearts could visualize a coronary artery of 50 µm in diameter. However, in vivo rat SRCA poses the problem of compromised temporal resolution due to the rapid heart rate of rats. PURPOSE To establish a simple method of in vivo rat SRCA with bradycardia induced by intravenous injection of adenosine triphosphate disodium hydrate (ATP). MATERIAL AND METHODS SRCA was performed at the Photon Factory of the High Energy Accelerator Research Organization (Tsukuba, Japan). Eight male Wistar rats were anesthetized. A catheter for injecting the contrast material was inserted into the carotid artery. Temporary bradycardia was induced by an intravenous bolus injection of 5 mg of ATP, and SRCA was performed immediately thereafter. RESULTS After ATP administration, the average heart rate decreased from 388 to 73 beats per minute. As a result, we could detect a coronary artery as small as 45 µm in diameter. CONCLUSION Our SRCA system which has a high resolution of 9 µm per pixel could detect a coronary artery as small as 45 µm in diameter in the in vivo rat.
Collapse
Affiliation(s)
- Hiroaki Sakamoto
- Department of Cardiovascular Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | | | - Kazuyuki Hyodo
- Photon Factory, High Energy Accelerator Research Organization, Tsukuba, Japan
| | - Chiho Tokunaga
- Department of Cardiovascular Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Fujio Sato
- Department of Cardiovascular Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Yuji Hiramatsu
- Department of Cardiovascular Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| |
Collapse
|
32
|
Abstract
Research studies on the three-dimensional (3D) morphological alterations of the spinal cord microvasculature after injury provide insight into the pathology of spinal cord injury (SCI). Knowledge in this field has been hampered in the past by imaging technologies that provided only two-dimensional (2D) information on the vascular reactions to trauma. The aim of our study is to investigate the 3D microstructural changes of the rat spinal cord microvasculature on day 1 post-injury using synchrotron radiation micro-tomography (SRμCT). This technology provides high-resolution 3D images of microvasculature in both normal and injured spinal cords, and the smallest vessel detected is approximately 7.4 μm. Moreover, we optimized the 3D vascular visualization with color coding and accurately calculated quantitative changes in vascular architecture after SCI. Compared to the control spinal cord, the damaged spinal cord vessel numbers decreased significantly following injury. Furthermore, the area of injury did not remain concentrated at the epicenter; rather, the signs of damage expanded rostrally and caudally along the spinal cord in 3D. The observed pathological changes were also confirmed by histological tests. These results demonstrate that SRμCT is an effective technology platform for imaging pathological changes in small arteries in neurovascular disease and for evaluating therapeutic interventions.
Collapse
|
33
|
Waddingham MT, Edgley AJ, Tsuchimochi H, Kelly DJ, Shirai M, Pearson JT. Contractile apparatus dysfunction early in the pathophysiology of diabetic cardiomyopathy. World J Diabetes 2015; 6:943-960. [PMID: 26185602 PMCID: PMC4499528 DOI: 10.4239/wjd.v6.i7.943] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 12/30/2014] [Accepted: 03/09/2015] [Indexed: 02/05/2023] Open
Abstract
Diabetes mellitus significantly increases the risk of cardiovascular disease and heart failure in patients. Independent of hypertension and coronary artery disease, diabetes is associated with a specific cardiomyopathy, known as diabetic cardiomyopathy (DCM). Four decades of research in experimental animal models and advances in clinical imaging techniques suggest that DCM is a progressive disease, beginning early after the onset of type 1 and type 2 diabetes, ahead of left ventricular remodeling and overt diastolic dysfunction. Although the molecular pathogenesis of early DCM still remains largely unclear, activation of protein kinase C appears to be central in driving the oxidative stress dependent and independent pathways in the development of contractile dysfunction. Multiple subcellular alterations to the cardiomyocyte are now being highlighted as critical events in the early changes to the rate of force development, relaxation and stability under pathophysiological stresses. These changes include perturbed calcium handling, suppressed activity of aerobic energy producing enzymes, altered transcriptional and posttranslational modification of membrane and sarcomeric cytoskeletal proteins, reduced actin-myosin cross-bridge cycling and dynamics, and changed myofilament calcium sensitivity. In this review, we will present and discuss novel aspects of the molecular pathogenesis of early DCM, with a special focus on the sarcomeric contractile apparatus.
Collapse
|
34
|
Sonobe T, Tsuchimochi H, Schwenke DO, Pearson JT, Shirai M. Treadmill running improves hindlimb arteriolar endothelial function in type 1 diabetic mice as visualized by X-ray microangiography. Cardiovasc Diabetol 2015; 14:51. [PMID: 25964060 PMCID: PMC4430879 DOI: 10.1186/s12933-015-0217-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 04/18/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Vascular function is impaired in patients with diabetes, however diabetic vascular dysfunction is ameliorated by exercise training. We aimed to clarify which hindlimb arterial segments are affected by treadmill running in the hindlimbs of streptozocin-induced type 1 diabetic mice in vivo. METHODS Mice were divided into 3 groups; healthy control, diabetic control, and diabetic-running groups. The exercise regimen was performed by treadmill level running mice for 60 min/day, for 4 weeks. Thereafter, we examined the vascular response to systemic acetylcholine administration in the left hindlimb of anesthetized-ventilated mice using either 1) X-ray microangiography to visualize the arteries or 2) ultrasonic flowmetry to record the femoral arterial blood flow. RESULTS X-ray imaging clearly visualized the hindlimb arterial network (~70-250 μm diameter). The vasodilator response to acetylcholine was significantly attenuated locally in the arterioles <100 μm diameter in the diabetic group of mice compared to the control group of mice. Post-acetylcholine administration, all groups showed an increase in hindlimb vascular conductance, but the diabetic mice showed the smallest increase. Overall, compared to the diabetic mice, the treadmill-running mice exhibited a significant enhancement of the vasodilator response within the arterioles with diabetes-induced vasodilator dysfunction. CONCLUSIONS Diabetes impaired acetylcholine-induced vasodilator function locally in the arteries <100 μm diameter and decreased hindlimb vascular conductance responded to acetylcholine, while regular treadmill running significantly ameliorated the impaired vasodilator function, and enhanced the decreased conductance in the diabetic mice.
Collapse
Affiliation(s)
- Takashi Sonobe
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
| | - Daryl O Schwenke
- Department of Physiology-Heart Otago, University of Otago, Dunedin, New Zealand.
| | - James T Pearson
- Department of Physiology, and Monash Biomedical Imaging Facility, Monash University, Melbourne, Australia. .,Australian Synchrotron, Clayton, Australia.
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
| |
Collapse
|
35
|
Lin X, Miao P, Mu Z, Jiang Z, Lu Y, Guan Y, Chen X, Xiao T, Wang Y, Yang GY. Development of functional in vivo imaging of cerebral lenticulostriate artery using novel synchrotron radiation angiography. Phys Med Biol 2015; 60:1655-65. [PMID: 25632958 DOI: 10.1088/0031-9155/60/4/1655] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The lenticulostriate artery plays a vital role in the onset and development of cerebral ischemia. However, current imaging techniques cannot assess the in vivo functioning of small arteries such as the lenticulostriate artery in the brain of rats. Here, we report a novel method to achieve a high resolution multi-functional imaging of the cerebrovascular system using synchrotron radiation angiography, which is based on spatio-temporal analysis of contrast density in the arterial cross section. This method provides a unique tool for studying the sub-cortical vascular elasticity after cerebral ischemia in rats. Using this technique, we demonstrated that the vascular elasticity of the lenticulostriate artery decreased from day 1 to day 7 after transient middle cerebral artery occlusion in rats and recovered from day 7 to day 28 compared to the controls (p < 0.001), which paralleled with brain edema formation and inversely correlated with blood flow velocity (p < 0.05). Our results demonstrated that the change of vascular elasticity was related to the levels of brain edema and the velocity of focal blood flow, suggesting that reducing brain edema is important for the improvement of the function of the lenticulostriate artery in the ischemic brain.
Collapse
Affiliation(s)
- Xiaojie Lin
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Higuchi T, Miyagawa S, Pearson JT, Fukushima S, Saito A, Tsuchimochi H, Sonobe T, Fujii Y, Yagi N, Astolfo A, Shirai M, Sawa Y. Functional and Electrical Integration of Induced Pluripotent Stem Cell-Derived Cardiomyocytes in a Myocardial Infarction Rat Heart. Cell Transplant 2015; 24:2479-89. [PMID: 25606821 DOI: 10.3727/096368914x685799] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In vitro expanded beating cardiac myocytes derived from induced pluripotent stem cells (iPSC-CMs) are a promising source of therapy for cardiac regeneration. Meanwhile, the cell sheet method has been shown to potentially maximize survival, functionality, and integration of the transplanted cells into the heart. It is thus hypothesized that transplanted iPSC-CMs in a cell sheet manner may contribute to functional recovery via direct mechanical effects on the myocardial infarction (MI) heart. F344/NJcl-rnu/rnu rats were left coronary artery ligated (n = 30), followed by transplantation of Dsred-labeled iPSC-CM cell sheets of murine origin over the infarct heart surface. Effects of the treatment were assessed, including in vivo molecular/cellular evaluations using a synchrotron radiation scattering technique. Ejection fraction and activation recovery interval were significantly greater from day 3 onward after iPSC-CM transplantation compared to those after sham operation. A number of transplanted iPSC-CMs were present on the heart surface expressing cardiac myosin or connexin 43 over 2 weeks, assessed by immunoconfocal microscopy, while mitochondria in the transplanted iPSC-CMs gradually showed mature structure as assessed by electron microscopy. Of note, X-ray diffraction identified 1,0 and 1,1 equatorial reflections attributable to myosin and actin-myosin lattice planes typical of organized cardiac muscle fibers within the transplanted cell sheets at 4 weeks, suggesting cyclic systolic myosin mass transfer to actin filaments in the transplanted iPSC-CMs. Transplantation of iPSC-CM cell sheets into the heart yielded functional and electrical recovery with cyclic contraction of transplanted cells in the rat MI heart, indicating that this strategy may be a promising cardiac muscle replacement therapy.
Collapse
Affiliation(s)
- Takahiro Higuchi
- Department of Cardiac Surgery, Osaka University Graduate School of Medicine, Osaka, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Cell-sheet therapy with omentopexy promotes arteriogenesis and improves coronary circulation physiology in failing heart. Mol Ther 2014; 23:374-86. [PMID: 25421595 DOI: 10.1038/mt.2014.225] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 11/16/2014] [Indexed: 12/25/2022] Open
Abstract
Cell-sheet transplantation induces angiogenesis for chronic myocardial infarction (MI), though insufficient capillary maturation and paucity of arteriogenesis may limit its therapeutic effects. Omentum has been used clinically to promote revascularization and healing of ischemic tissues. We hypothesized that cell-sheet transplantation covered with an omentum-flap would effectively establish mature blood vessels and improve coronary microcirculation physiology, enhancing the therapeutic effects of cell-sheet therapy. Rats were divided into four groups after coronary ligation; skeletal myoblast cell-sheet plus omentum-flap (combined), cell-sheet only, omentum-flap only, and sham operation. At 4 weeks after the treatment, the combined group showed attenuated cardiac hypertrophy and fibrosis, and a greater amount of functionally (CD31(+)/lectin(+)) and structurally (CD31(+)/α-SMA(+)) mature blood vessels, along with myocardial upregulation of relevant genes. Synchrotron-based microangiography revealed that the combined procedure increased vascularization in resistance arterial vessels with better dilatory responses to endothelium-dependent agents. Serial (13)N-ammonia PET showed better global coronary flow reserve in the combined group, mainly attributed to improvement in the basal left ventricle. Consequently, the combined group had sustained improvements in cardiac function parameters and better functional capacity. Cell-sheet transplantation with an omentum-flap better promoted arteriogenesis and improved coronary microcirculation physiology in ischemic myocardium, leading to potent functional recovery in the failing heart.
Collapse
|
38
|
Drenjancevic I, Koller A, Selthofer-Relatic K, Grizelj I, Cavka A. Assessment of coronary hemodynamics and vascular function. Prog Cardiovasc Dis 2014; 57:423-30. [PMID: 25460847 DOI: 10.1016/j.pcad.2014.11.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Coronary blood flow closely matches to metabolic demands of heart and myocardial oxygen consumption and is conditioned by function of coronary resistance vessels. The microvascular endothelium of coronary resistance vessels is exposed to a spatially and temporally regulated input from cardiomyocytes and the haemodynamic forces of the cardiac cycle. Functional measurements of coronary pressure and flow are important approaches that provide complementary information on the function of coronary vessel function that could not be assessed by the methods utilized for the anatomic characterization of coronary disease, such as coronary angiography. The goal of this paper is to review the methodologies for assessment of coronary vascular function and haemodynamics which are utilized in research and to discuss their potential applicability in the clinical settings.
Collapse
Affiliation(s)
- Ines Drenjancevic
- Faculty of Medicine Osijek, University of Osijek, Department of Physiology and Immunology, Osijek, Croatia.
| | - Akos Koller
- Department of Physiology and Gerontology, Medical School and Szentagothai Research Centre, University of Pecs, Hungary, Department of Pathophysiology, Semmelweis University, Budapest, Hungary, Department of Physiology New York Medical College, Valhalla NY 10595, USA; Walhala University NW, USA
| | - Kristina Selthofer-Relatic
- Faculty of Medicine Osijek, University of Osijek, Dept of Internal Medicine, Osijek, Croatia; Clinical Hospital Center Osijek, Clinic for Internal Diseases, Osijek, Croatia
| | - Ivana Grizelj
- Faculty of Medicine Osijek, University of Osijek, Department of Physiology and Immunology, Osijek, Croatia
| | - Ana Cavka
- Faculty of Medicine Osijek, University of Osijek, Department of Physiology and Immunology, Osijek, Croatia
| |
Collapse
|
39
|
Zhang M, Peng G, Sun D, Xie Y, Xia J, Long H, Hu K, Xiao B. Synchrotron radiation imaging is a powerful tool to image brain microvasculature. Med Phys 2014; 41:031907. [PMID: 24593725 DOI: 10.1118/1.4865784] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Synchrotron radiation (SR) imaging is a powerful experimental tool for micrometer-scale imaging of microcirculation in vivo. This review discusses recent methodological advances and findings from morphological investigations of cerebral vascular networks during several neurovascular pathologies. In particular, it describes recent developments in SR microangiography for real-time assessment of the brain microvasculature under various pathological conditions in small animal models. It also covers studies that employed SR-based phase-contrast imaging to acquire 3D brain images and provide detailed maps of brain vasculature. In addition, a brief introduction of SR technology and current limitations of SR sources are described in this review. In the near future, SR imaging could transform into a common and informative imaging modality to resolve subtle details of cerebrovascular function.
Collapse
Affiliation(s)
- Mengqi Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Guanyun Peng
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
| | - Danni Sun
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Yuanyuan Xie
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Jian Xia
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Hongyu Long
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Kai Hu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| |
Collapse
|
40
|
Yuan F, Lin X, Guan Y, Mu Z, Chen K, Wang Y, Yang GY. Collateral circulation prevents masticatory muscle impairment in rat middle cerebral artery occlusion model. JOURNAL OF SYNCHROTRON RADIATION 2014; 21:1314-1318. [PMID: 25343800 DOI: 10.1107/s1600577514016130] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 07/11/2014] [Indexed: 06/04/2023]
Abstract
The rat suture middle cerebral artery occlusion (MCAO) is a frequently used animal model for investigating the mechanisms of ischemic brain injury. During suture MCAO, transection of the external carotid artery (ECA) potentially restrains blood flow and impairs masticatory muscle and other ECA-supported territories, consequently influencing post-operation animal survival. This study was aimed at investigating the effect of ECA transection on the hemodynamic alterations using a novel synchrotron radiation (SR) angiography technique and magnetic resonance imaging in live animals. Fifteen male adult Sprague-Dawley rats were used in this study. Animals underwent MCAO, in which the ECA was transected. SR angiography was performed before and after MCAO. Rats then underwent magnetic resonance imaging (MRI) to detect the tissue lesion both intra- and extra-cranially. Animals with SR angiography without other manipulations were used as control. High-resolution cerebrovascular morphology was analyzed using a novel technique of SR angiography. The masticatory muscle lesion was further examined by hematoxylin and eosin staining. MRI and histological results showed that there was no masticatory muscle lesion at 1, 7 and 28 days following MCAO with ECA transection. In normal condition, the ECA and its branch external maxillary artery were clearly detected. Following ECA transection, the external maxillary artery was still observed and the blood supply appeared from the anastomotic branch from the pterygopalatine artery. SR angiography further revealed the inter-relationship of hemisphere extra- and intra-cranial vasculature in the rat following MCAO. Transection of the ECA did not impair masticatory muscles in rat suture MCAO. Interrupted blood flow could be compensated by the collateral circulation from the pterygopalatine artery.
Collapse
Affiliation(s)
- Falei Yuan
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| | - Xiaojie Lin
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| | - Yongjing Guan
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, People's Republic of China
| | - Zhihao Mu
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| | - Kemin Chen
- Department of Radiology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, People's Republic of China
| | - Yongting Wang
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| | - Guo-Yuan Yang
- Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, People's Republic of China
| |
Collapse
|
41
|
Nagai H, Kuwahira I, Schwenke DO, Tsuchimochi H, Nara A, Inagaki T, Ogura S, Fujii Y, Umetani K, Shimosawa T, Yoshida KI, Pearson JT, Uemura K, Shirai M. β2-Adrenergic receptor-dependent attenuation of hypoxic pulmonary vasoconstriction prevents progression of pulmonary arterial hypertension in intermittent hypoxic rats. PLoS One 2014; 9:e110693. [PMID: 25350545 PMCID: PMC4211686 DOI: 10.1371/journal.pone.0110693] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 09/15/2014] [Indexed: 11/19/2022] Open
Abstract
In sleep apnea syndrome (SAS), intermittent hypoxia (IH) induces repeated episodes of hypoxic pulmonary vasoconstriction (HPV) during sleep, which presumably contribute to pulmonary arterial hypertension (PAH). However, the prevalence of PAH was low and severity is mostly mild in SAS patients, and mild or no right ventricular hypertrophy (RVH) was reported in IH-exposed animals. The question then arises as to why PAH is not a universal finding in SAS if repeated hypoxia of sufficient duration causes cycling HPV. In the present study, rats underwent IH at a rate of 3 min cycles of 4-21% O2 for 8 h/d for 6 w. Assessment of diameter changes in small pulmonary arteries in response to acute hypoxia and drugs were performed using synchrotron radiation microangiography on anesthetized rats. In IH-rats, neither PAH nor RVH was observed and HPV was strongly reversed. Nadolol (a hydrophilic β(1, 2)-blocker) augmented the attenuated HPV to almost the same level as that in N-rats, but atenolol (a hydrophilic β1-blocker) had no effect on the HPV in IH. These β-blockers had almost no effect on the HPV in N-rats. Chronic administration of nadolol during 6 weeks of IH exposure induced PAH and RVH in IH-rats, but did not in N-rats. Meanwhile, atenolol had no effect on morphometric and hemodynamic changes in N and IH-rats. Protein expression of the β1-adrenergic receptor (AR) was down-regulated while that of β2AR was preserved in pulmonary arteries of IH-rats. Phosphorylation of p85 (chief component of phosphoinositide 3-kinase (PI3K)), protein kinase B (Akt), and endothelial nitric oxide synthase (eNOS) were abrogated by chronic administration of nadolol in the lung tissue of IH-rats. We conclude that IH-derived activation of β2AR in the pulmonary arteries attenuates the HPV, thereby preventing progression of IH-induced PAH. This protective effect may depend on the β2AR-Gi mediated PI3K/Akt/eNOS signaling pathway.
Collapse
Affiliation(s)
- Hisashi Nagai
- Department of Forensic Medicine, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Forensic Medicine, The University of Tokyo, Tokyo, Japan
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
- * E-mail:
| | - Ichiro Kuwahira
- Department of Pulmonary Medicine, Tokai University Tokyo Hospital, Tokyo, Japan
| | - Daryl O. Schwenke
- Department of Physiology-Heart Otago, University of Otago, Dunedin, New Zealand
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Akina Nara
- Department of Forensic Medicine, The University of Tokyo, Tokyo, Japan
| | - Tadakatsu Inagaki
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Sayoko Ogura
- Department of Forensic Medicine, The University of Tokyo, Tokyo, Japan
- Division of Laboratory Medicine, Department of Pathology and Microbiology, Faculty of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Yutaka Fujii
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Hyogo, Japan
| | - Tatsuo Shimosawa
- Department of Clinical Laboratory Medicine, The University of Tokyo, Tokyo, Japan
| | - Ken-ichi Yoshida
- Department of Forensic Medicine, The University of Tokyo, Tokyo, Japan
- Department of Forensic Medicine, Tokyo Medical University, Tokyo, Japan
| | - James T. Pearson
- Monash Biomedical Imaging Facility and Department of Physiology, Monash University, Melbourne, Clayton, Victoria, Australia
- Australian Synchrotron, Clayton, Victoria, Australia
| | - Koichi Uemura
- Department of Forensic Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| |
Collapse
|
42
|
Shirai M, Tsuchimochi H, Nagai H, Gray E, Pearson JT, Sonobe T, Yoshimoto M, Inagaki T, Fujii Y, Umetani K, Kuwahira I, Schwenke DO. Pulmonary vascular tone is dependent on the central modulation of sympathetic nerve activity following chronic intermittent hypoxia. Basic Res Cardiol 2014; 109:432. [PMID: 25139633 DOI: 10.1007/s00395-014-0432-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/03/2014] [Accepted: 08/04/2014] [Indexed: 11/24/2022]
Abstract
Chronic intermittent hypoxia (IH) provokes a centrally mediated increase in sympathetic nerve activity (SNA). Although this sympathetic hyperexcitation has been linked to systemic hypertension, its effect on the pulmonary vasculature is unclear. This study aimed to assess IH-mediated sympathetic excitation in modulating pulmonary vasculature tone, particularly acute hypoxia vasoconstrictor response (HPV), and the central β-adrenergic signaling pathway for facilitating the increase in SNA. Sprague-Dawley rats were exposed to IH (cycle of 4% O2 for 90 s/air for 90 s) for 8 h/day for 6 weeks. Subsequently, rats were anesthetized and either pulmonary SNA was recorded (electrophysiology), or the pulmonary vasculature was visualized using microangiography. Pulmonary sympathetic and vascular responses to acute hypoxia were assessed before and after central β1-adrenergic receptor blockade (Metoprolol, 200 nmol i.c.v.). Chronic IH increased baseline SNA (110% increase), and exacerbated the sympathetic response to acute hypoxia. Moreover, the magnitude of HPV in IH rats was blunted compared to control rats (e.g., 10 and 20% vasoconstriction, respectively). In only the IH rats, β1-receptor blockade with metoprolol attenuated the hypoxia-induced increase in pSNA and exacerbated the magnitude of acute HPV, so that both sympathetic and HPV responses were similar to that of control rats. Interestingly, the expression of β1-receptors within the brainstem was similar between both control and IH rats. These results suggest that the centrally mediated increase in SNA following IH acts to blunt the local vasoconstrictor effect of acute hypoxia, which reflects an inherent difference between vasodilator and vasoconstrictor actions of SNA in pulmonary and systemic circulations.
Collapse
Affiliation(s)
- Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Zhang MQ, Sun DN, Xie YY, Peng GY, Xia J, Long HY, Xiao B. Three-dimensional visualization of rat brain microvasculature following permanent focal ischaemia by synchrotron radiation. BJR Case Rep 2014. [DOI: 10.1259/bjrcr.20130670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
|
44
|
Zhang MQ, Sun DN, Xie YY, Peng GY, Xia J, Long HY, Xiao B. Three-dimensional visualization of rat brain microvasculature following permanent focal ischaemia by synchrotron radiation. Br J Radiol 2014; 87:20130670. [PMID: 24702152 DOI: 10.1259/bjr.20130670] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVE Identifying morphological changes that occur in microvessels under both normal and ischaemic conditions is crucial for understanding and treating stroke. However, conventional imaging techniques are not able to detect microvessels on a micron or sub-micron scale without angiography. In the present study, synchrotron radiation (SR)-based X-ray in-line phase contrast imaging (ILPCI) was used to acquire high-resolution and high-contrast images of rat brain tissues in both normal and ischaemic states. METHODS ILPCI was performed at the Shanghai Synchrotron Radiation Facility, Shanghai, China, without the use of contrast agents. CT slices were reformatted and then converted into three-dimensional (3D) reconstruction images to analyse subtle details of the cerebral microvascular network. RESULTS By using ILPCI, brain vessels up to 11.8 μm in diameter were resolved. The number of cortical and penetrating arteries detected were found to undergo a remarkable decrease within the infarct area. 3 days after permanent ischaemia, vascular masses were also observed in the peripheral region of the infarcts. CONCLUSION SR-based ILPCI-CT can serve as a powerful tool to accurately visualize brain microvasculature. The morphological parameters of blood vessels in both CT slices and 3D reconstructions were determined, and this approach has great potential for providing an effective diagnosis and evaluation for rehabilitation therapy for stroke. ADVANCES IN KNOWLEDGE In the absence of contrast agent, the 3D morphologies of the brain microvasculature in normal and stroke rats were obtained using SR-based ILPCI. SR imaging is a sensitive and promising method which can be used to explore primary brain function.
Collapse
Affiliation(s)
- M Q Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | | | | | | | | | | | | |
Collapse
|
45
|
Establishment of a novel murine model of ischemic cardiomyopathy with multiple diffuse coronary lesions. PLoS One 2013; 8:e70755. [PMID: 23950999 PMCID: PMC3741297 DOI: 10.1371/journal.pone.0070755] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 06/22/2013] [Indexed: 12/04/2022] Open
Abstract
Objectives Atherosclerotic lesions of the coronary arteries are the pathological basis for myocardial infarction and ischemic cardiomyopathy. Progression of heart failure after myocardial infarction is associated with cardiac remodeling, which has been studied by means of coronary ligation in mice. However, this ligation model requires excellent techniques. Recently, a new murine model, HypoE mouse was reported to exhibit atherogenic Paigen diet-induced coronary atherosclerosis and myocardial infarction; however, the HypoE mice died too early to make possible investigation of cardiac remodeling. Therefore, we aimed to modify the HypoE mouse model to establish a novel model for ischemic cardiomyopathy caused by atherosclerotic lesions, which the ligation model does not exhibit. Methods and Results In our study, the sustained Paigen diet for the HypoE mice was shortened to 7 or 10 days, allowing the mice to survive longer. The 7-day Paigen diet intervention starting when the mice were 8 weeks old was adequate to permit the mice to survive myocardial infarction. Our murine model, called the “modified HypoE mouse”, was maintained until 8 weeks, with a median survival period of 36 days, after the dietary intervention (male, n = 222). Echocardiography demonstrated that the fractional shortening 2 weeks after the Paigen diet (n = 14) significantly decreased compared with that just before the Paigen diet (n = 6) (31.4±11.9% vs. 54.4±2.6%, respectively, P<0.01). Coronary angiography revealed multiple diffuse lesions. Cardiac remodeling and fibrosis were identified by serial analyses of cardiac morphological features and mRNA expression levels in tissue factors such as MMP-2, MMP-9, TIMP-1, collagen-1, and TGF-β. Conclusion Modified HypoE mice are a suitable model for ischemic cardiomyopathy with multiple diffuse lesions and may be considered as a novel and convenient model for investigations of cardiac remodeling on a highly atherogenic background.
Collapse
|