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Sedaghati F, Dixon JB, Gleason RL. A 1D model characterizing the role of spatiotemporal contraction distributions on lymph transport. Sci Rep 2023; 13:21241. [PMID: 38040740 PMCID: PMC10692214 DOI: 10.1038/s41598-023-48131-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 11/22/2023] [Indexed: 12/03/2023] Open
Abstract
Lymphedema is a condition in which lymph transport is compromised. The factors that govern the timing of lymphatic contractions are largely unknown; however, these factors likely play a central role in lymphatic health. Computational models have proven useful in quantifying changes in lymph transport; nevertheless, there is still much unknown regarding the regulation of contractions. The purpose of this paper is to utilize computational modeling to examine the role of pacemaking activity in lymph transport. A 1D fluid-solid modeling framework was utilized to describe the interaction between the contracting vessel and the lymph flow. The distribution of contractions along a three-lymphangion chain in time and space was determined by specifying the pacemaking sites and parameters obtained from experimentation. The model effectively replicates the contractility patterns in experiments. Quantitatively, the flow rates were measured at 5.44 and 2.29 [Formula: see text], and the EF values were 78% and less than 33% in the WT and KO models, respectively, which are consistent with the literature. Applying pacemaking parameters in this modeling framework effectively captures lymphatic contractile wave propagations and their relation to lymph transport. It can serve as a motivation for conducting novel studies to evaluate lymphatic pumping function during the development of lymphedema.
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Affiliation(s)
- Farbod Sedaghati
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - J Brandon Dixon
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- The Wallace H. Coulter Georgia Tech/Emory Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Rudolph L Gleason
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
- The Wallace H. Coulter Georgia Tech/Emory Department of Biomedical Engineering, Georgia Institute of Technology, 387 Technology Circle, Room 216F, Atlanta, GA, 30313, USA.
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2
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Cheon H, Lee SH, Kim SA, Kim B, Suh HP, Jeon JY. In Vivo Dynamic and Static Analysis of Lymphatic Dysfunction in Lymphedema Using Near-Infrared Fluorescence Indocyanine Green Lymphangiography. Arterioscler Thromb Vasc Biol 2023; 43:2008-2022. [PMID: 37615112 DOI: 10.1161/atvbaha.123.319188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 08/02/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND Near-infrared fluorescence indocyanine green lymphangiography, a primary modality for detecting lymphedema, which is a disease due to lymphatic obstruction, enables real-time observations of lymphatics and reveals not only the spatial distribution of drainage (static analysis) but also information on the lymphatic contraction (dynamic analysis). METHODS We have produced total lymphatic obstruction in the upper limbs of 18 Sprague-Dawley rats through the dissection of proximal (brachial and axillary) lymph nodes and 20-Gy radiation (dissection limbs). After the model formation for 1 week, 9 animal models were observed for 6 weeks using near-infrared fluorescence indocyanine green lymphangiography by injecting 6-μL ICG-BSA (indocyanine green-bovine serum albumin) solution of 20-μg/mL concentration. The drainage pattern and leakage of lymph fluid were evaluated and time-domain signals of lymphatic contraction were observed in the distal lymphatic vessels. The obtained signals were converted to frequency-domain spectrums using signal processing. RESULTS The results of both static and dynamic analyses proved to be effective in accurately identifying the extent of lymphatic disruption in the dissection limbs. The static analysis showed abnormal drainage patterns and increased leakage of lymph fluid to the periphery of the vessels compared with the control (normal) limbs. Meanwhile, the waveforms were changed and the contractile signal frequency increased by 58% in the dynamic analysis. Specifically, our findings revealed that regular lymphatic contractions, observed at a frequency range of 0.08 to 0.13 Hz in the control limbs, were absent in the dissection limbs. The contractile regularity was not fully restored for the follow-up period, indicating a persistent lymphatic obstruction. CONCLUSIONS The dynamic analysis could detect the abnormalities of lymphatic circulation by observing the characteristics of signals, and it provided additional evaluation indicators that cannot be provided by the static analysis. Our findings may be useful for the early detection of the circulation problem as a functional evaluation indicator of the lymphatic system.
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Affiliation(s)
- Hwayeong Cheon
- Biomedical Engineering Research Center, Asan Medical Center, Seoul, Republic of Korea (H.C.)
| | - Sang-Hun Lee
- Department of Optical Engineering, Kumoh National Institute of Technology, Gyeongbuk, Republic of Korea (S.-H.L.)
| | - Sang Ah Kim
- Department of Rehabilitation Medicine (S.A.K., B.K., J.Y.J.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Bumchul Kim
- Department of Rehabilitation Medicine (S.A.K., B.K., J.Y.J.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hyunsuk Peter Suh
- Department of Plastic Surgery (H.P.S.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jae Yong Jeon
- Department of Rehabilitation Medicine (S.A.K., B.K., J.Y.J.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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3
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Breslin JW. Lymphatic Clearance and Pump Function. Cold Spring Harb Perspect Med 2023; 13:a041187. [PMID: 35667711 PMCID: PMC9899645 DOI: 10.1101/cshperspect.a041187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lymphatic vessels have an active role in draining excess interstitial fluid from organs and serving as conduits for immune cell trafficking to lymph nodes. In the central circulation, the force needed to propel blood forward is generated by the heart. In contrast, lymphatic vessels rely on intrinsic vessel contractions in combination with extrinsic forces for lymph propulsion. The intrinsic pumping features phasic contractions generated by lymphatic smooth muscle. Periodic, bicuspid valves composed of endothelial cells prevent backflow of lymph. This work provides a brief overview of lymph transport, including initial lymph formation along with cellular and molecular mechanisms controlling lymphatic vessel pumping.
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Affiliation(s)
- Jerome W Breslin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, USA
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4
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Davis MJ, Kim HJ, Nichols CG. K ATP channels in lymphatic function. Am J Physiol Cell Physiol 2022; 323:C1018-C1035. [PMID: 35785984 PMCID: PMC9550566 DOI: 10.1152/ajpcell.00137.2022] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 06/22/2022] [Accepted: 06/23/2022] [Indexed: 11/22/2022]
Abstract
KATP channels function as negative regulators of active lymphatic pumping and lymph transport. This review summarizes and critiques the evidence for the expression of specific KATP channel subunits in lymphatic smooth muscle and endothelium, the roles that they play in normal lymphatic function, and their possible involvement in multiple diseases, including metabolic syndrome, lymphedema, and Cantú syndrome. For each of these topics, suggestions are made for directions for future research.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri
| | - Hae Jin Kim
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri
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5
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Morris CJ, Zawieja DC, Moore JE. A multiscale sliding filament model of lymphatic muscle pumping. Biomech Model Mechanobiol 2021; 20:2179-2202. [PMID: 34476656 PMCID: PMC8595193 DOI: 10.1007/s10237-021-01501-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 08/01/2021] [Indexed: 11/30/2022]
Abstract
The lymphatics maintain fluid balance by returning interstitial fluid to veins via contraction/compression of vessel segments with check valves. Disruption of lymphatic pumping can result in a condition called lymphedema with interstitial fluid accumulation. Lymphedema treatments are often ineffective, which is partially attributable to insufficient understanding of specialized lymphatic muscle lining the vessels. This muscle exhibits cardiac-like phasic contractions and smooth muscle-like tonic contractions to generate and regulate flow. To understand the relationship between this sub-cellular contractile machinery and organ-level pumping, we have developed a multiscale computational model of phasic and tonic contractions in lymphatic muscle and coupled it to a lymphangion pumping model. Our model uses the sliding filament model (Huxley in Prog Biophys Biophys Chem 7:255-318, 1957) and its adaptation for smooth muscle (Mijailovich in Biophys J 79(5):2667-2681, 2000). Multiple structural arrangements of contractile components and viscoelastic elements were trialed but only one provided physiologic results. We then coupled this model with our previous lumped parameter model of the lymphangion to relate results to experiments. We show that the model produces similar pressure, diameter, and flow tracings to experiments on rat mesenteric lymphatics. This model provides the first estimates of lymphatic muscle contraction energetics and the ability to assess the potential effects of sub-cellular level phenomena such as calcium oscillations on lymphangion outflow. The maximum efficiency value predicted (40%) is at the upper end of estimates for other muscle types. Spontaneous calcium oscillations during diastole were found to increase outflow up to approximately 50% in the range of frequencies and amplitudes tested.
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Affiliation(s)
- Christopher J Morris
- Department of Bioengineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - David C Zawieja
- College of Medicine Faculty, Texas A&M University, Texas, USA
| | - James E Moore
- Department of Bioengineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
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6
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Elich H, Barrett A, Shankar V, Fogelson AL. Pump efficacy in a two-dimensional, fluid-structure interaction model of a chain of contracting lymphangions. Biomech Model Mechanobiol 2021; 20:1941-1968. [PMID: 34275062 DOI: 10.1007/s10237-021-01486-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 06/26/2021] [Indexed: 11/25/2022]
Abstract
The transport of lymph through the lymphatic vasculature is the mechanism for returning excess interstitial fluid to the circulatory system, and it is essential for fluid homeostasis. Collecting lymphatic vessels comprise a significant portion of the lymphatic vasculature and are divided by valves into contractile segments known as lymphangions. Despite its importance, lymphatic transport in collecting vessels is not well understood. We present a computational model to study lymph flow through chains of valved, contracting lymphangions. We used the Navier-Stokes equations to model the fluid flow and the immersed boundary method to handle the two-way, fluid-structure interaction in 2D, non-axisymmetric simulations. We used our model to evaluate the effects of chain length, contraction style, and adverse axial pressure difference (AAPD) on cycle-mean flow rates (CMFRs). In the model, longer lymphangion chains generally yield larger CMFRs, and they fail to generate positive CMFRs at higher AAPDs than shorter chains. Simultaneously contracting pumps generate the largest CMFRs at nearly every AAPD and for every chain length. Due to the contraction timing and valve dynamics, non-simultaneous pumps generate lower CMFRs than the simultaneous pumps; the discrepancy diminishes as the AAPD increases. Valve dynamics vary with the contraction style and exhibit hysteretic opening and closing behaviors. Our model provides insight into how contraction propagation affects flow rates and transport through a lymphangion chain.
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Affiliation(s)
- Hallie Elich
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA.
| | - Aaron Barrett
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
| | - Varun Shankar
- School of Computing, University of Utah, Salt Lake City, UT, USA
| | - Aaron L Fogelson
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
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7
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Hu D, Li L, Li S, Wu M, Ge N, Cui Y, Lian Z, Song J, Chen H. Lymphatic system identification, pathophysiology and therapy in the cardiovascular diseases. J Mol Cell Cardiol 2019; 133:99-111. [PMID: 31181226 DOI: 10.1016/j.yjmcc.2019.06.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/02/2019] [Accepted: 06/05/2019] [Indexed: 12/20/2022]
Abstract
The mammalian circulatory system comprises both the cardiovascular system and the lymphatic system. In contrast to the closed, high-pressure and circular blood vascular circulation, the lymphatic system forms an open, low-pressure and unidirectional transit network from the extracellular space to the venous system. It plays a key role in regulating tissue fluid homeostasis, absorption of gastrointestinal lipids, and immune surveillance throughout the body. Despite the critical physiological functions of the lymphatic system, a complete understanding of the lymphatic vessels lags far behind that of the blood vasculatures due to the challenge of their visualization. During the last 20 years, discoveries of underlying genes responsible for lymphatic vessel biology, combined with state-of-the-art lymphatic function imaging and quantification techniques, have established the importance of the lymphatic vasculature in the pathogenesis of cardiovascular diseases including lymphedema, obesity and metabolic diseases, dyslipidemia, hypertension, inflammation, atherosclerosis and myocardial infraction. In this review, we highlight the most recent advances in the field of lymphatic vessel biology, with an emphasis on the new identification techniques of lymphatic system, pathophysiological mechanisms of atherosclerosis and myocardial infarction, and new therapeutic perspectives of lymphangiogenesis.
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Affiliation(s)
- Dan Hu
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Long Li
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Sufang Li
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Manyan Wu
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Nana Ge
- Department of Geriatrics, Beijing Renhe Hospital, Beijing, China
| | - Yuxia Cui
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Zheng Lian
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Junxian Song
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China
| | - Hong Chen
- Department of Cardiology, Beijing Key Laboratory of Early Prediction and Intervention of Acute Myocardial Infarction, Center for Cardiovascular Translational Research, Peking University People's Hospital, Beijing, China.
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8
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Zawieja SD, Castorena JA, Gui P, Li M, Bulley SA, Jaggar JH, Rock JR, Davis MJ. Ano1 mediates pressure-sensitive contraction frequency changes in mouse lymphatic collecting vessels. J Gen Physiol 2019; 151:532-554. [PMID: 30862712 PMCID: PMC6445586 DOI: 10.1085/jgp.201812294] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 02/06/2019] [Indexed: 12/16/2022] Open
Abstract
Lymphatic collecting vessels exhibit spontaneous contractions with a pressure-dependent contraction frequency. The initiation of contraction has been proposed to be mediated by the activity of a Ca2+-activated Cl- channel (CaCC). Here, we show that the canonical CaCC Anoctamin 1 (Ano1, TMEM16a) plays an important role in lymphatic smooth muscle pacemaking. We find that isolated murine lymphatic muscle cells express Ano1, and demonstrate functional CaCC currents that can be inhibited by the Ano1 inhibitor benzbromarone. These currents are absent in lymphatic muscle cells from Cre transgenic mouse lines targeted for Ano1 genetic deletion in smooth muscle. We additionally show that loss of functional Ano1 in murine inguinal-axillary lymphatic vessels, whether through genetic manipulation or pharmacological inhibition, results in an impairment of the pressure-frequency relationship that is attributable to a hyperpolarized resting membrane potential and a significantly depressed diastolic depolarization rate preceding each action potential. These changes are accompanied by alterations in action potential shape and duration, and a reduced duration but increased amplitude of the action potential-induced global "Ca2+ flashes" that precede lymphatic contractions. These findings suggest that an excitatory Cl- current provided by Ano1 is critical for mediating the pressure-sensitive contractile response and is a major component of the murine lymphatic action potential.
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Affiliation(s)
- Scott D Zawieja
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Jorge A Castorena
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Peichun Gui
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Min Li
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
| | - Simon A Bulley
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN
| | - Jonathan H Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN
| | - Jason R Rock
- Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO
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9
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Breslin JW, Yang Y, Scallan JP, Sweat RS, Adderley SP, Murfee WL. Lymphatic Vessel Network Structure and Physiology. Compr Physiol 2018; 9:207-299. [PMID: 30549020 PMCID: PMC6459625 DOI: 10.1002/cphy.c180015] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The lymphatic system is comprised of a network of vessels interrelated with lymphoid tissue, which has the holistic function to maintain the local physiologic environment for every cell in all tissues of the body. The lymphatic system maintains extracellular fluid homeostasis favorable for optimal tissue function, removing substances that arise due to metabolism or cell death, and optimizing immunity against bacteria, viruses, parasites, and other antigens. This article provides a comprehensive review of important findings over the past century along with recent advances in the understanding of the anatomy and physiology of lymphatic vessels, including tissue/organ specificity, development, mechanisms of lymph formation and transport, lymphangiogenesis, and the roles of lymphatics in disease. © 2019 American Physiological Society. Compr Physiol 9:207-299, 2019.
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Affiliation(s)
- Jerome W. Breslin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Ying Yang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Joshua P. Scallan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Richard S. Sweat
- Department of Biomedical Engineering, Tulane University, New Orleans, LA
| | - Shaquria P. Adderley
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - W. Lee Murfee
- Department of Biomedical Engineering, University of Florida, Gainesville, FL
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10
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Castorena-Gonzalez JA, Zawieja SD, Li M, Srinivasan RS, Simon AM, de Wit C, de la Torre R, Martinez-Lemus LA, Hennig GW, Davis MJ. Mechanisms of Connexin-Related Lymphedema. Circ Res 2018; 123:964-985. [PMID: 30355030 PMCID: PMC6771293 DOI: 10.1161/circresaha.117.312576] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
RATIONALE Mutations in GJC2 and GJA1, encoding Cxs (connexins) 47 and 43, respectively, are linked to lymphedema, but the underlying mechanisms are unknown. Because efficient lymph transport relies on the coordinated contractions of lymphatic muscle cells (LMCs) and their electrical coupling through Cxs, Cx-related lymphedema is proposed to result from dyssynchronous contractions of lymphatic vessels. OBJECTIVE To determine which Cx isoforms in LMCs and lymphatic endothelial cells are required for the entrainment of lymphatic contraction waves and efficient lymph transport. METHODS AND RESULTS We developed novel methods to quantify the spatiotemporal entrainment of lymphatic contraction waves and used optogenetic techniques to analyze calcium signaling within and between the LMC and the lymphatic endothelial cell layers. Genetic deletion of the major lymphatic endothelial cell Cxs (Cx43, Cx47, or Cx37) revealed that none were necessary for the synchronization of the global calcium events that triggered propagating contraction waves. We identified Cx45 in human and mouse LMCs as the critical Cx mediating the conduction of pacemaking signals and entrained contractions. Smooth muscle-specific Cx45 deficiency resulted in 10- to 18-fold reduction in conduction speed, partial-to-severe loss of contractile coordination, and impaired lymph pump function ex vivo and in vivo. Cx45 deficiency resulted in profound inhibition of lymph transport in vivo, but only under an imposed gravitational load. CONCLUSIONS Our results (1) identify Cx45 as the Cx isoform mediating the entrainment of the contraction waves in LMCs; (2) show that major endothelial Cxs are dispensable for the entrainment of contractions; (3) reveal a lack of coupling between lymphatic endothelial cells and LMCs, in contrast to arterioles; (4) point to lymphatic valve defects, rather than contraction dyssynchrony, as the mechanism underlying GJC2- or GJA1-related lymphedema; and (5) show that a gravitational load exacerbates lymphatic contractile defects in the intact mouse hindlimb, which is likely critical for the development of lymphedema in the adult mouse.
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Affiliation(s)
| | - Scott D. Zawieja
- Dept. of Medical Pharmacology and Physiology and University of Missouri School of Medicine
| | - Min Li
- Dept. of Medical Pharmacology and Physiology and University of Missouri School of Medicine
| | - R. Sathish Srinivasan
- Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City OK
| | | | - Cor de Wit
- Institute of Physiology, University of Luebeck, Luebeck Germany
| | | | - Luis A. Martinez-Lemus
- Dept. of Medical Pharmacology and Physiology and University of Missouri School of Medicine
| | | | - Michael J. Davis
- Dept. of Medical Pharmacology and Physiology and University of Missouri School of Medicine
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11
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Zawieja SD, Castorena-Gonzalez JA, Dixon B, Davis MJ. Experimental Models Used to Assess Lymphatic Contractile Function. Lymphat Res Biol 2018; 15:331-342. [PMID: 29252142 DOI: 10.1089/lrb.2017.0052] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Recent years have seen a renewed interest in studies of the lymphatic system. This review addresses the differences between in vivo and ex vivo methods for visualization and functional studies of lymphatic networks, with an emphasis on studies of collecting lymphatic vessels. We begin with a brief summary of the historical uses of both approaches. For the purpose of detailed comparisons, we subdivide in vivo methods into those visualizing lymphatic networks through the intact skin and those using surgically opened skin. We subdivide ex vivo methods into isobaric studies (using a pressure myograph) or isometric studies (using a wire myograph). For all four categories, we compile a comprehensive list of the advantages, disadvantages, and limitations of each preparation, with the goal of informing the research community as to the appropriate kinds of experiments best suited, and ill suited, for each.
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Affiliation(s)
- Scott D Zawieja
- 1 Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri
| | | | - Brandon Dixon
- 2 George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology , Atlanta, Georgia
| | - Michael J Davis
- 1 Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri
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12
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Zawieja SD, Castorena-Gonzalez JA, Scallan JP, Davis MJ. Differences in L-type Ca 2+ channel activity partially underlie the regional dichotomy in pumping behavior by murine peripheral and visceral lymphatic vessels. Am J Physiol Heart Circ Physiol 2018; 314:H991-H1010. [PMID: 29351458 DOI: 10.1152/ajpheart.00499.2017] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We identified a regional dichotomy in murine lymphatic contractile function with regard to vessel location within the periphery or visceral cavity. All vessels isolated from peripheral regions [cervical, popliteal, inguinal, axillary, and internodal inguinal axillary (Ing-Ax)] developed robust contractions with maximal ejection fractions (EFs) of 50-80% in our ex vivo isobaric myograph experiments. Conversely, vessels isolated from the visceral cavity (mesenteric, thoracic duct, and iliac) demonstrated maximal EFs of ≤10%. Using pressure myography, sharp electrode membrane potential recordings, and Ca2+ imaging, we assessed the role of L-type Ca2+ channels in this contractile dichotomy. Ing-Ax membrane potential revealed a ~2-s action potential (AP) cycle (resting -35 mV, spike -5 mV, and plateau -11 mV) with a plateau phase that was significantly lengthened by the L-type Ca2+ channel agonist Bay K8644 (BayK; 100 nM). APs recorded from mesenteric vessels, however, displayed a slower upstroke and an elongated time over threshold. BayK (100 nM) increased the mesenteric AP upstroke velocity and plateau duration but also significantly hyperpolarized the vessel. Contractions of vessels from both regions were preceded by Ca2+ flashes, detected with a smooth muscle-specific endogenous Ca2+ reporter, that typically were coordinated over the length of the vessel. Similar to the membrane potential recordings, Ca2+ flashes in mesenteric vessels were weaker and had a slower rise time but were longer lasting than those in Ing-Ax vessels. BayK (100 nM) significantly increased the Ca2+ transient amplitude and duration in both vessels and decreased time to peak Ca2+ in mesenteric vessels. However, a higher concentration (1 μM) of BayK was required to produce even a modest increase in EF in visceral lymphatics, which remained at <20%. NEW & NOTEWORTHY Lymphatic collecting vessels isolated from murine peripheral tissues, but not from the visceral cavities, display robust contractile behavior similar to lymphatic vessels from other animal models and humans. These differences are partially explained by L-type Ca2+ channel activity as revealed by the first measurements of murine lymphatic action potentials and contraction-associated Ca2+ transients.
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Affiliation(s)
- Scott D Zawieja
- Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri
| | | | - Joshua P Scallan
- Molecular Pharmacology and Physiology, University of South Florida , Tampa, Florida
| | - Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri
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13
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Hasselhof V, Sperling A, Buttler K, Ströbel P, Becker J, Aung T, Felmerer G, Wilting J. Morphological and Molecular Characterization of Human Dermal Lymphatic Collectors. PLoS One 2016; 11:e0164964. [PMID: 27764183 PMCID: PMC5072738 DOI: 10.1371/journal.pone.0164964] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 10/04/2016] [Indexed: 01/20/2023] Open
Abstract
Millions of patients suffer from lymphedema worldwide. Supporting the contractility of lymphatic collectors is an attractive target for pharmacological therapy of lymphedema. However, lymphatics have mostly been studied in animals, while the cellular and molecular characteristics of human lymphatic collectors are largely unknown. We studied epifascial lymphatic collectors of the thigh, which were isolated for autologous transplantations. Our immunohistological studies identify additional markers for LECs (vimentin, CCBE1). We show and confirm differences between initial and collecting lymphatics concerning the markers ESAM1, D2-40 and LYVE-1. Our transmission electron microscopic studies reveal two types of smooth muscle cells (SMCs) in the media of the collectors with dark and light cytoplasm. We observed vasa vasorum in the media of the largest collectors, as well as interstitial Cajal-like cells, which are highly ramified cells with long processes, caveolae, and lacking a basal lamina. They are in close contact with SMCs, which possess multiple caveolae at the contact sites. Immunohistologically we identified such cells with antibodies against vimentin and PDGFRα, but not CD34 and cKIT. With Next Generation Sequencing we searched for highly expressed genes in the media of lymphatic collectors, and found therapeutic targets, suitable for acceleration of lymphatic contractility, such as neuropeptide Y receptors 1, and 5; tachykinin receptors 1, and 2; purinergic receptors P2RX1, and 6, P2RY12, 13, and 14; 5-hydroxytryptamine receptors HTR2B, and 3C; and adrenoceptors α2A,B,C. Our studies represent the first comprehensive characterization of human epifascial lymphatic collectors, as a prerequisite for diagnosis and therapy.
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Affiliation(s)
- Viktoria Hasselhof
- Institute of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
| | - Anastasia Sperling
- Institute of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
| | - Kerstin Buttler
- Institute of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
| | - Philipp Ströbel
- Institute of Pathology, University Medical Center Göttingen, Göttingen, Germany
| | - Jürgen Becker
- Institute of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
| | - Thiha Aung
- Division of Trauma Surgery, Plastic and Reconstructive Surgery, University Medical Center Göttingen, Göttingen, Germany
- Center of Plastic, Hand and Reconstructive Surgery, University Medical Center Regensburg, Regensburg, Germany
| | - Gunther Felmerer
- Division of Trauma Surgery, Plastic and Reconstructive Surgery, University Medical Center Göttingen, Göttingen, Germany
| | - Jörg Wilting
- Institute of Anatomy and Cell Biology, University Medical School Göttingen, Göttingen, Germany
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15
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Scallan JP, Davis MJ. Itching for answers: how histamine relaxes lymphatic vessels. Microcirculation 2015; 21:575-7. [PMID: 25123019 DOI: 10.1111/micc.12162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 08/08/2014] [Indexed: 11/27/2022]
Abstract
In the current issue of Microcirculation, studies by Kurtz et al. and Nizamutdinova et al. together provide new evidence supporting a role for histamine as an endothelial-derived molecule that inhibits lymphatic muscle contraction. In particular, Nizamutdinova et al. show that the effects of flow-induced shear stress on lymphatic endothelium are mediated by both nitric oxide and histamine, since only blockade of both prevents contraction strength and frequency from being altered by flow. Separately, Kurtz et al. used confocal microscopy to determine a preferential expression of histamine receptors on the lymphatic endothelium and demonstrated that histamine applied to spontaneously contracting collecting lymphatics inhibits contractions. Previous studies disagreed on whether histamine stimulates or inhibits lymphatic contractions, but also used differing concentrations, species, and preparations. Together these new reports shed light on how histamine acts within the lymphatic vasculature, but also raise important questions about the cell type on which histamine exerts its effects and the signaling pathways involved. This editorial briefly discusses the contribution of each study and its relevance to lymphatic biology.
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Affiliation(s)
- Joshua P Scallan
- Department of Medical Pharmacology & Physiology, University of Missouri, Columbia, Missouri
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16
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Dongaonkar RM, Nguyen TL, Quick CM, Heaps CL, Hardy J, Laine GA, Wilson E, Stewart RH. Mesenteric lymphatic vessels adapt to mesenteric venous hypertension by becoming weaker pumps. Am J Physiol Regul Integr Comp Physiol 2014; 308:R391-9. [PMID: 25519727 DOI: 10.1152/ajpregu.00196.2014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lymphangions, the segments of lymphatic vessels between two adjacent lymphatic valves, actively pump lymph. Acute changes in transmural pressure and lymph flow have profound effects on lymphatic pump function in vitro. Chronic changes in pressure and flow in vivo have also been reported to lead to significant changes in lymphangion function. Because changes in pressure and flow are both cause and effect of adaptive processes, characterizing adaptation requires a more fundamental analysis of lymphatic muscle properties. Therefore, the purpose of the present work was to use an intact lymphangion isovolumetric preparation to evaluate changes in mesenteric lymphatic muscle mechanical properties and the intracellular Ca(2+) in response to sustained mesenteric venous hypertension. Bovine mesenteric veins were surgically occluded to create mesenteric venous hypertension. Postnodal mesenteric lymphatic vessels from mesenteric venous hypertension (MVH; n = 6) and sham surgery (Sham; n = 6) animals were isolated and evaluated 3 days after the surgery. Spontaneously contracting MVH vessels generated end-systolic active tension and end-diastolic active tension lower than the Sham vessels. Furthermore, steady-state active tension and intracellular Ca(2+) concentration levels in response to KCl stimulation were also significantly lower in MVH vessels compared with those of the Sham vessels. There was no significant difference in passive tension in lymphatic vessels from the two groups. Taken together, these results suggest that following 3 days of mesenteric venous hypertension, postnodal mesenteric lymphatic vessels adapt to become weaker pumps with decreased cytosolic Ca(2+) concentration.
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Affiliation(s)
- R M Dongaonkar
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas
| | - T L Nguyen
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas
| | - C M Quick
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas;
| | - C L Heaps
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas
| | - J Hardy
- Large Animal Clinical Sciences, Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas; and
| | - G A Laine
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas
| | - E Wilson
- Department of Medical Physiology, Texas A&M Health Science Center, Texas A&M University, College Station, Texas
| | - R H Stewart
- Michael E. DeBakey Institute, Texas A&M University, College Station, Texas
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17
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Breslin JW. Mechanical forces and lymphatic transport. Microvasc Res 2014; 96:46-54. [PMID: 25107458 DOI: 10.1016/j.mvr.2014.07.013] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 07/29/2014] [Indexed: 10/24/2022]
Abstract
This review examines the current understanding of how the lymphatic vessel network can optimize lymph flow in response to various mechanical forces. Lymphatics are organized as a vascular tree, with blind-ended initial lymphatics, precollectors, prenodal collecting lymphatics, lymph nodes, postnodal collecting lymphatics and the larger trunks (thoracic duct and right lymph duct) that connect to the subclavian veins. The formation of lymph from interstitial fluid depends heavily on oscillating pressure gradients to drive fluid into initial lymphatics. Collecting lymphatics are segmented vessels with unidirectional valves, with each segment, called a lymphangion, possessing an intrinsic pumping mechanism. The lymphangions propel lymph forward against a hydrostatic pressure gradient. Fluid is returned to the central circulation both at lymph nodes and via the larger lymphatic trunks. Several recent developments are discussed, including evidence for the active role of endothelial cells in lymph formation; recent developments on how inflow pressure, outflow pressure, and shear stress affect the pump function of the lymphangion; lymphatic valve gating mechanisms; collecting lymphatic permeability; and current interpretations of the molecular mechanisms within lymphatic endothelial cells and smooth muscle. An improved understanding of the physiological mechanisms by which lymphatic vessels sense mechanical stimuli, integrate the information, and generate the appropriate response is key for determining the pathogenesis of lymphatic insufficiency and developing treatments for lymphedema.
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Affiliation(s)
- Jerome W Breslin
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
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Blei F. Update December 2013. Lymphat Res Biol 2013. [DOI: 10.1089/lrb.2013.1142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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