1
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Chen J, Ding Y, Chen M, Gau J, Jen N, Nahal C, Tu S, Chen C, Zhou S, Chang CC, Lyu J, Xu X, Hsiai TK, Packard RRS. Displacement analysis of myocardial mechanical deformation (DIAMOND) reveals segmental susceptibility to doxorubicin-induced injury and regeneration. JCI Insight 2019; 4:125362. [PMID: 30996130 PMCID: PMC6538350 DOI: 10.1172/jci.insight.125362] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/27/2019] [Indexed: 12/27/2022] Open
Abstract
Zebrafish are increasingly utilized to model cardiomyopathies and regeneration. Current methods evaluating cardiac function have known limitations, fail to reliably detect focal mechanics, and are not readily feasible in zebrafish. We developed a semiautomated, open-source method - displacement analysis of myocardial mechanical deformation (DIAMOND) - for quantitative assessment of 4D segmental cardiac function. We imaged transgenic embryonic zebrafish in vivo using a light-sheet fluorescence microscopy system with 4D cardiac motion synchronization. Our method permits the derivation of a transformation matrix to quantify the time-dependent 3D displacement of segmental myocardial mass centroids. Through treatment with doxorubicin, and by chemically and genetically manipulating the myocardial injury-activated Notch signaling pathway, we used DIAMOND to demonstrate that basal ventricular segments adjacent to the atrioventricular canal display the highest 3D displacement and are also the most susceptible to doxorubicin-induced injury. Thus, DIAMOND provides biomechanical insights into in vivo segmental cardiac function scalable to high-throughput research applications.
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Affiliation(s)
- Junjie Chen
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Yichen Ding
- Division of Cardiology, Department of Medicine, David Geffen School of Medicine
| | - Michael Chen
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Jonathan Gau
- Division of Cardiology, Department of Medicine, David Geffen School of Medicine
| | - Nelson Jen
- Division of Cardiology, Department of Medicine, David Geffen School of Medicine
| | - Chadi Nahal
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Sally Tu
- Department of Neuroscience, College of Letters and Science, University of California, Los Angeles, California, USA
| | - Cynthia Chen
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Steve Zhou
- Division of Cardiology, Department of Medicine, David Geffen School of Medicine
| | - Chih-Chiang Chang
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Jintian Lyu
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
| | - Xiaolei Xu
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Tzung K. Hsiai
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Sciences
- Division of Cardiology, Department of Medicine, David Geffen School of Medicine
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2
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Baek KI, Li R, Jen N, Choi H, Kaboodrangi A, Ping P, Liem D, Beebe T, Hsiai TK. Flow-Responsive Vascular Endothelial Growth Factor Receptor-Protein Kinase C Isoform Epsilon Signaling Mediates Glycolytic Metabolites for Vascular Repair. Antioxid Redox Signal 2018; 28:31-43. [PMID: 28762754 PMCID: PMC5695747 DOI: 10.1089/ars.2017.7044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 07/31/2017] [Accepted: 07/31/2017] [Indexed: 12/19/2022]
Abstract
AIMS Hemodynamic shear stress participates in maintaining vascular redox status. Elucidating flow-mediated endothelial metabolites enables us to discover metabolic biomarkers and therapeutic targets. We posited that flow-responsive vascular endothelial growth factor receptor (VEGFR)-protein kinase C isoform epsilon (PKCɛ)-6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) signaling modulates glycolytic metabolites for vascular repair. RESULTS Bidirectional oscillatory flow (oscillatory shear stress [OSS]: 0.1 ± 3 dyne·cm-2 at 1 Hz) upregulated VEGFR-dependent PKCɛ expression to a greater degree than did unidirectional pulsatile flow (pulsatile shear stress [PSS]: 23 ± 8 dyne·cm-2 at 1 Hz) in human aortic endothelial cells (p < 0.05, n = 3). PSS and OSS further upregulated PKCɛ-dependent PFKFB3 expression for glycolysis (p < 0.05, n = 4). Constitutively active PKCɛ increased, whereas dominant-negative PKCɛ reduced both basal and maximal extracellular acidification rates for glycolytic flux (p < 0.01, n = 4). Metabolomic analysis demonstrated an increase in PKCɛ-dependent glycolytic metabolite, dihydroxyacetone (DHA), but a decrease in gluconeogenic metabolite, aspartic acid (p < 0.05 vs. control, n = 6). In a New Zealand White rabbit model, both PKCɛ and PFKFB3 immunostaining was prominent in the PSS- and OSS-exposed aortic arch and descending aorta. In a transgenic Tg(flk-1:EGFP) zebrafish model, GATA-1a morpholino oligonucleotide injection (to reduce viscosity-dependent shear stress) impaired vascular regeneration after tail amputation (p < 0.01, n = 20), which was restored with PKCɛ messenger RNA (mRNA) rescue (p < 0.05, n = 5). As a corollary, siPKCɛ inhibited tube formation and vascular repair, which were restored by DHA treatment in our Matrigel and zebrafish models. Innovation and Conclusion: Flow-sensitive VEGFR-PKCɛ-PFKFB3 signaling increases the glycolytic metabolite, dihydroxyacetone, to promote vascular repair. Antioxid. Redox Signal. 28, 31-43.
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Affiliation(s)
- Kyung In Baek
- 1 Department of Bioengineering, School of Engineering and Applied Science, University of California , Los Angeles, Los Angeles, California
| | - Rongsong Li
- 2 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
| | - Nelson Jen
- 1 Department of Bioengineering, School of Engineering and Applied Science, University of California , Los Angeles, Los Angeles, California
| | - Howard Choi
- 2 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
| | - Amir Kaboodrangi
- 1 Department of Bioengineering, School of Engineering and Applied Science, University of California , Los Angeles, Los Angeles, California
| | - Peipei Ping
- 2 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
- 3 Department of Physiology, School of Medicine, University of California , Los Angeles, Los Angeles, California
| | - David Liem
- 2 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
| | - Tyler Beebe
- 1 Department of Bioengineering, School of Engineering and Applied Science, University of California , Los Angeles, Los Angeles, California
| | - Tzung K Hsiai
- 1 Department of Bioengineering, School of Engineering and Applied Science, University of California , Los Angeles, Los Angeles, California
- 2 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
- 3 Department of Physiology, School of Medicine, University of California , Los Angeles, Los Angeles, California
- 4 Greater Los Angeles VA Healthcare System , Los Angeles, California
- 5 Department of Medical Engineering, California Institute of Technology , Pasadena, California
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3
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Packard RRS, Luo Y, Abiri P, Jen N, Aksoy O, Suh WM, Tai YC, Hsiai TK. 3-D Electrochemical Impedance Spectroscopy Mapping of Arteries to Detect Metabolically Active but Angiographically Invisible Atherosclerotic Lesions. Am J Cancer Res 2017; 7:2431-2442. [PMID: 28744325 PMCID: PMC5525747 DOI: 10.7150/thno.19184] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 04/18/2017] [Indexed: 11/18/2022] Open
Abstract
We designed a novel 6-point electrochemical impedance spectroscopy (EIS) sensor with 15 combinations of permutations for the 3-D mapping and detection of metabolically active atherosclerotic lesions. Two rows of 3 stretchable electrodes circumferentially separated by 120° were mounted on an inflatable balloon for intravascular deployment and endoluminal interrogation. The configuration and 15 permutations of 2-point EIS electrodes allowed for deep arterial penetration via alternating current (AC) to detect varying degrees of lipid burden with distinct impedance profiles (Ω). By virtue of the distinctive impedimetric signature of metabolically active atherosclerotic lesions, a detailed impedance map was acquired, with the 15 EIS permutations uncovering early stages of disease characterized by fatty streak lipid accumulation in the New Zealand White rabbit model of atherosclerosis. Both the equivalent circuit and statistical analyses corroborated the 3-D EIS permutations to detect small, angiographically invisible, lipid-rich lesions, with translational implications for early atherosclerotic disease detection and prevention of acute coronary syndromes or strokes.
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Baek KI, Li R, Liem D, Beebe T, Ma J, Choi H, Jen N, Yen H, Ping P, Hsiai TK. Abstract 614: Shear Stress-Induced Glycolytic Metabolites Promote Vascular Repair. Arterioscler Thromb Vasc Biol 2017. [DOI: 10.1161/atvb.37.suppl_1.614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
Hemodynamic shear stress is intimately linked with transcriptomic and epigenomic changes to maintain endothelial homeostasis. Metabolomics studies have led to emergent metabolic biomarkers and therapeutic targets. Whether shear stress modulates metabolomic pathway to promote vascular repair remains to be investigated.
Hypothesis:
We hypothesized that shear stress regulates VEGF receptor-PKCε-PFKFB3 signaling-mediated glycolytic metabolites to promote vascular repair.
Method and Results:
Both pulsatile (PSS: 23 ± 8 dyn·cm
-2
at 1 Hz) and oscillatory shear stress (OSS: 0.1 ± 3 dyn·cm
-2
at 1 Hz) up-regulated PKCε expressions and the activity (*
P
< 0.05,
n
=3), whereas silencing VEGFR2 with siRNA, or treating with VEGFR inhibitor, Cediranib, attenuated shear stress-mediated PKCε expression in human aortic endothelial cells(HAEC). Constitutively active (CA)-PKCε adenovirus infection enhanced tube formation assessed by Matrigel as well as significantly increased PFKFB3 expressions promoting glycolysis, whereas the dominant negative(DN) PKCε resulted in opposite effects. Co-localization of PKCε and PFKFB3 expression was demonstrated in the endothelium of aortic arch and thoracic aorta in a New Zealand White rabbit model. In the zebrafish tail amputation model, reduction of shear stress via
GATA-1a
morpholino oligonucleotide(MO) injection and inhibition of PKCε expression via PKCε MO impaired vascular repair between the dorsal aorta and the dorsal longitudinal anastomotic vessel at 3 days post amputation(dpa). PKCε mRNA rescued
GATA-1a
MO-mediated impairment of vascular repair (*
P
< 0.01,
n
=20, **
P
< 0.05,
n
=5). Metabolomic analysis in HAEC applied to PSS and OSS revealed modulation of a number of metabolites including increased glycolytic metabolite dihydroxyacetone, which was blocked by PKCε siRNA. Treatment with dihydroxyacetone rescued PKCε-impaired vascular repair.
Conclusion:
In conclusion, shear stress-mediated VEGFR-PKCε-PFKFB3 signaling increased glycolytic metabolites to mediate vascular repair.
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5
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Li R, Yang J, Saffari A, Jacobs J, Baek KI, Hough G, Larauche MH, Ma J, Jen N, Moussaoui N, Zhou B, Kang H, Reddy S, Henning SM, Campen MJ, Pisegna J, Li Z, Fogelman AM, Sioutas C, Navab M, Hsiai TK. Ambient Ultrafine Particle Ingestion Alters Gut Microbiota in Association with Increased Atherogenic Lipid Metabolites. Sci Rep 2017; 7:42906. [PMID: 28211537 PMCID: PMC5314329 DOI: 10.1038/srep42906] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 01/17/2017] [Indexed: 12/22/2022] Open
Abstract
Ambient particulate matter (PM) exposure is associated with atherosclerosis and inflammatory bowel disease. Ultrafine particles (UFP, dp < 0.1–0.2 μm) are redox active components of PM. We hypothesized that orally ingested UFP promoted atherogenic lipid metabolites in both the intestine and plasma via altered gut microbiota composition. Low density lipoprotein receptor-null (Ldlr−/−) mice on a high-fat diet were orally administered with vehicle control or UFP (40 μg/mouse/day) for 3 days a week. After 10 weeks, UFP ingested mice developed macrophage and neutrophil infiltration in the intestinal villi, accompanied by elevated cholesterol but reduced coprostanol levels in the cecum, as well as elevated atherogenic lysophosphatidylcholine (LPC 18:1) and lysophosphatidic acids (LPAs) in the intestine and plasma. At the phylum level, Principle Component Analysis revealed significant segregation of microbiota compositions which was validated by Beta diversity analysis. UFP-exposed mice developed increased abundance in Verrocomicrobia but decreased Actinobacteria, Cyanobacteria, and Firmicutes as well as a reduced diversity in microbiome. Spearman’s analysis negatively correlated Actinobacteria with cecal cholesterol, intestinal and plasma LPC18:1, and Firmicutes and Cyanobacteria with plasma LPC 18:1. Thus, ultrafine particles ingestion alters gut microbiota composition, accompanied by increased atherogenic lipid metabolites. These findings implicate the gut-vascular axis in a atherosclerosis model.
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Affiliation(s)
- Rongsong Li
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Jieping Yang
- Division of Clinical Nutrition, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Arian Saffari
- Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Jonathan Jacobs
- Division of Gastroenterology and Hepatology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Kyung In Baek
- Department of Bioengineering, School of Engineering &Applied Science, University of California, Los Angeles, CA 90095, USA
| | - Greg Hough
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Muriel H Larauche
- Division of Gastroenterology and Hepatology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Jianguo Ma
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA.,Department of Bioengineering, School of Engineering &Applied Science, University of California, Los Angeles, CA 90095, USA
| | - Nelson Jen
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA.,Department of Bioengineering, School of Engineering &Applied Science, University of California, Los Angeles, CA 90095, USA
| | - Nabila Moussaoui
- Division of Gastroenterology and Hepatology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Bill Zhou
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Hanul Kang
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Srinivasa Reddy
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Susanne M Henning
- Division of Clinical Nutrition, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Matthew J Campen
- Department of Pharmaceutical Sciences, School of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
| | - Joseph Pisegna
- Division of Gastroenterology and Hepatology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Zhaoping Li
- Division of Clinical Nutrition, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Alan M Fogelman
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Constantinos Sioutas
- Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90089, USA
| | - Mohamad Navab
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Tzung K Hsiai
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, CA 90095, USA.,Department of Bioengineering, School of Engineering &Applied Science, University of California, Los Angeles, CA 90095, USA
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Lee J, Fei P, Sevag Packard RR, Kang H, Xu H, Baek KI, Jen N, Chen J, Yen H, Kuo CCJ, Chi NC, Ho CM, Li R, Hsiai TK. 4-Dimensional light-sheet microscopy to elucidate shear stress modulation of cardiac trabeculation. J Clin Invest 2016; 126:3158. [PMID: 27479748 DOI: 10.1172/jci89549] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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7
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Lee J, Fei P, Packard RRS, Kang H, Xu H, Baek KI, Jen N, Chen J, Yen H, Kuo CCJ, Chi NC, Ho CM, Li R, Hsiai TK. 4-Dimensional light-sheet microscopy to elucidate shear stress modulation of cardiac trabeculation. J Clin Invest 2016; 126:1679-90. [PMID: 27018592 DOI: 10.1172/jci83496] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 02/09/2016] [Indexed: 12/14/2022] Open
Abstract
Hemodynamic shear forces are intimately linked with cardiac development, during which trabeculae form a network of branching outgrowths from the myocardium. Mutations that alter Notch signaling also result in trabeculation defects. Here, we assessed whether shear stress modulates trabeculation to influence contractile function. Specifically, we acquired 4D (3D + time) images with light sheets by selective plane illumination microscopy (SPIM) for rapid scanning and deep axial penetration during zebrafish morphogenesis. Reduction of blood viscosity via gata1a morpholino oligonucleotides (MO) reduced shear stress, resulting in downregulation of Notch signaling and attenuation of trabeculation. Arrest of cardiomyocyte contraction either by troponin T type 2a (tnnt2a) MO or in weak atriumm58 (wea) mutants resulted in reduced shear stress and downregulation of Notch signaling and trabeculation. Integrating 4D SPIM imaging with synchronization algorithm demonstrated that coinjection of neuregulin1 mRNA with gata1 MO rescued trabeculation to restore contractile function in association with upregulation of Notch-related genes. Crossbreeding of Tg(flk:mCherry) fish, which allows visualization of the vascular system with the Tg(tp1:gfp) Notch reporter line, revealed that shear stress-mediated Notch activation localizes to the endocardium. Deleting endocardium via the clochesk4 mutants downregulated Notch signaling, resulting in nontrabeculated ventricle. Subjecting endothelial cells to pulsatile flow in the presence of the ADAM10 inhibitor corroborated shear stress-activated Notch signaling to modulate trabeculation.
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8
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Guan Z, Lee J, Jiang H, Dong S, Jen N, Hsiai T, Ho CM, Fei P. Compact plane illumination plugin device to enable light sheet fluorescence imaging of multi-cellular organisms on an inverted wide-field microscope. Biomed Opt Express 2016; 7:194-208. [PMID: 26819828 PMCID: PMC4722903 DOI: 10.1364/boe.7.000194] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 12/06/2015] [Accepted: 12/08/2015] [Indexed: 05/05/2023]
Abstract
We developed a compact plane illumination plugin (PIP) device which enabled plane illumination and light sheet fluorescence imaging on a conventional inverted microscope. The PIP device allowed the integration of microscope with tunable laser sheet profile, fast image acquisition, and 3-D scanning. The device is both compact, measuring approximately 15 by 5 by 5 cm, and cost-effective, since we employed consumer electronics and an inexpensive device molding method. We demonstrated that PIP provided significant contrast and resolution enhancement to conventional microscopy through imaging different multi-cellular fluorescent structures, including 3-D branched cells in vitro and live zebrafish embryos. Imaging with the integration of PIP greatly reduced out-of-focus contamination and generated sharper contrast in acquired 2-D plane images when compared with the stand-alone inverted microscope. As a result, the dynamic fluid domain of the beating zebrafish heart was clearly segmented and the functional monitoring of the heart was achieved. Furthermore, the enhanced axial resolution established by thin plane illumination of PIP enabled the 3-D reconstruction of the branched cellular structures, which leads to the improvement on the functionality of the wide field microscopy.
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Affiliation(s)
- Zeyi Guan
- Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
- contributed equally
| | - Juhyun Lee
- Biomedical Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
- contributed equally
| | - Hao Jiang
- School of Mechanical and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Siyan Dong
- Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
| | - Nelson Jen
- Biomedical Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
| | - Tzung Hsiai
- Biomedical Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
- School of Medicine, University of California, Los Angeles, Los Angeles, 90095, USA
| | - Chih-Ming Ho
- Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
| | - Peng Fei
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
- Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, 90095, USA
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9
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Li R, Jen N, Wu L, Lee J, Fang K, Quigley K, Lee K, Wang S, Zhou B, Vergnes L, Chen YR, Li Z, Reue K, Ann DK, Hsiai TK. Disturbed Flow Induces Autophagy, but Impairs Autophagic Flux to Perturb Mitochondrial Homeostasis. Antioxid Redox Signal 2015; 23:1207-19. [PMID: 26120766 PMCID: PMC4657520 DOI: 10.1089/ars.2014.5896] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
AIM Temporal and spatial variations in shear stress are intimately linked with vascular metabolic effects. Autophagy is tightly regulated in intracellular bulk degradation/recycling system for maintaining cellular homeostasis. We postulated that disturbed flow modulates autophagy with an implication in mitochondrial superoxide (mtO2(•-)) production. RESULTS In the disturbed flow or oscillatory shear stress (OSS)-exposed aortic arch, we observed prominent staining of p62, a reverse marker of autophagic flux, whereas in the pulsatile shear stress (PSS)-exposed descending aorta, p62 was attenuated. OSS significantly increased (i) microtubule-associated protein light chain 3 (LC3) II to I ratios in human aortic endothelial cells, (ii) autophagosome formation as quantified by green fluorescent protein (GFP)-LC3 dots per cell, and (iii) p62 protein levels, whereas manganese superoxide dismutase (MnSOD) overexpression by recombinant adenovirus, N-acetyl cysteine treatment, or c-Jun N-terminal kinase (JNK) inhibition reduced OSS-mediated LC3-II/LC3-I ratios and mitochondrial DNA damage. Introducing bafilomycin to Earle's balanced salt solution or to OSS condition incrementally increased both LC3-II/LC3-I ratios and p62 levels, implicating impaired autophagic flux. In the OSS-exposed aortic arch, both anti-phospho-JNK and anti-8-hydroxy-2'-deoxyguanosine (8-OHdG) staining for DNA damage were prominent, whereas in the PSS-exposed descending aorta, the staining was nearly absent. Knockdown of ATG5 with siRNA increased OSS-mediated mtO2(•-), whereas starvation or rapamycin-induced autophagy reduced OSS-mediated mtO2(•-), mitochondrial respiration, and complex II activity. INNOVATION Disturbed flow-mediated oxidative stress and JNK activation induce autophagy. CONCLUSION OSS impairs autophagic flux to interfere with mitochondrial homeostasis. Antioxid. Redox Signal. 23, 1207-1219.
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Affiliation(s)
- Rongsong Li
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Nelson Jen
- 2 Department of Bioengineering, UCLA Henry Samueli School of Engineering and Applied Science , Los Angeles, California
| | - Lan Wu
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Juhyun Lee
- 2 Department of Bioengineering, UCLA Henry Samueli School of Engineering and Applied Science , Los Angeles, California
| | - Karen Fang
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Katherine Quigley
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Katherine Lee
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Sky Wang
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Bill Zhou
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Laurent Vergnes
- 3 Department of Human Genetics, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Yun-Ru Chen
- 4 Department of Molecular Pharmacology, Beckman Research Institute, City of Hope National Medical Center , Duarte, California
| | - Zhaoping Li
- 5 Department of Medicine, VA Greater Los Angeles Healthcare System, UCLA David Geffen School of Medicine , Los Angeles, California
| | - Karen Reue
- 3 Department of Human Genetics, UCLA David Geffen School of Medicine , Los Angeles, California
| | - David K Ann
- 4 Department of Molecular Pharmacology, Beckman Research Institute, City of Hope National Medical Center , Duarte, California
| | - Tzung K Hsiai
- 1 Division of Cardiology, Department of Medicine, UCLA David Geffen School of Medicine , Los Angeles, California.,2 Department of Bioengineering, UCLA Henry Samueli School of Engineering and Applied Science , Los Angeles, California.,5 Department of Medicine, VA Greater Los Angeles Healthcare System, UCLA David Geffen School of Medicine , Los Angeles, California
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Lee J, Cao H, Kang BJ, Jen N, Yu F, Lee CA, Fei P, Park J, Bohlool S, Lash-Rosenberg L, Shung KK, Hsiai TK. Hemodynamics and ventricular function in a zebrafish model of injury and repair. Zebrafish 2015; 11:447-54. [PMID: 25237983 DOI: 10.1089/zeb.2014.1016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Myocardial infarction results in scar tissue and irreversible loss of ventricular function. Unlike humans, zebrafish has the capacity to remove scar tissue after injury. To assess ventricular function during repair, we synchronized microelectrocardiogram (μECG) signals with a high-frequency ultrasound pulsed-wave (PW) Doppler to interrogate cardiac hemodynamics. μECG signals allowed for identification of PW Doppler signals for passive (early [E]-wave velocity) and active ventricular filling (atrial [A]-wave velocity) during diastole. The A wave (9.0±1.2 cm·s(-1)) is greater than the E wave (1.1±0.4 cm·s(-1)), resulting in an E/A ratio <1 (0.12±0.05, n=6). In response to cryocauterization to the ventricular epicardium, the E-wave velocity increased, accompanied by a rise in the E/A ratio at 3 days postcryocauterization (dpc) (0.55±0.13, n=6, p<0.001 vs. sham). The E waves normalize toward the baseline, along with a reduction in the E/A ratio at 35 dpc (0.36±0.06, n=6, p<0.001 vs. sham) and 65 dpc (0.2±0.16, n=6, p<0.001 vs. sham). In zebrafish, E/A<1 at baseline is observed, suggesting the distinct two-chamber system in which the pressure gradient across the atrioventricular valve is higher compared with the ventriculobulbar valve. The initial rise and subsequent normalization of E/A ratios support recovery in the ventricular diastolic function.
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Affiliation(s)
- Juhyun Lee
- 1 Division of Cardiology, Department of Medicine, University of California , Los Angeles, Los Angeles, California
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Li R, Navab K, Hough G, Daher N, Zhang M, Mittelstein D, Lee K, Pakbin P, Saffari A, Bhetraratana M, Sulaiman D, Beebe T, Wu L, Jen N, Wine E, Tseng CH, Araujo JA, Fogelman A, Sioutas C, Navab M, Hsiai TK. Effect of exposure to atmospheric ultrafine particles on production of free fatty acids and lipid metabolites in the mouse small intestine. Environ Health Perspect 2015; 123:34-41. [PMID: 25170928 PMCID: PMC4286268 DOI: 10.1289/ehp.1307036] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 08/27/2014] [Indexed: 05/09/2023]
Abstract
BACKGROUND Exposure to ambient ultrafine particulate matter (UFP) is a well-recognized risk factor for cardiovascular and respiratory diseases. However, little is known about the effects of air pollution on gastrointestinal disorders. OBJECTIVE We sought to assess whether exposure to ambient UFP (diameter < 180 nm) increased free fatty acids and lipid metabolites in the mouse small intestine. METHODS Ldlr-null mice were exposed to filtered air (FA) or UFP collected at an urban Los Angeles, California, site that was heavily affected by vehicular emissions; the exposure was carried out for 10 weeks in the presence or absence of D-4F, an apolipoprotein A-I mimetic peptide with antioxidant and anti-inflammation properties on a high-fat or normal chow diet. RESULTS Compared with FA, exposure to UFP significantly increased intestinal hydroxyeicosatetraenoic acids (HETEs), including 15-HETE, 12-HETE, 5-HETE, as well as hydroxyoctadecadienoic acids (HODEs), including 13-HODE and 9-HODE. Arachidonic acid (AA) and prostaglandin D2 (PGD2) as well as some of the lysophosphatidic acids (LPA) in the small intestine were also increased in response to UFP exposure. Administration of D-4F significantly reduced UFP-mediated increase in HETEs, HODEs, AA, PGD2, and LPA. Although exposure to UFP further led to shortened villus length accompanied by prominent macrophage and neutrophil infiltration into the intestinal villi, administration of D-4F mitigated macrophage infiltration. CONCLUSIONS Exposure to UFP promotes lipid metabolism, villus shortening, and inflammatory responses in mouse small intestine, whereas administration of D-4F attenuated these effects. Our findings provide a basis to further assess the mechanisms underlying UFP-mediated lipid metabolism in the digestive system with clinical relevance to gut homeostasis and diseases.
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Affiliation(s)
- Rongsong Li
- Division of Cardiology, Department of Medicine, School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
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Li R, Beebe T, Jen N, Yu F, Takabe W, Harrison M, Cao H, Lee J, Yang H, Han P, Wang K, Shimizu H, Chen J, Lien CL, Chi NC, Hsiai TK. Shear stress-activated Wnt-angiopoietin-2 signaling recapitulates vascular repair in zebrafish embryos. Arterioscler Thromb Vasc Biol 2014; 34:2268-75. [PMID: 25147335 DOI: 10.1161/atvbaha.114.303345] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Fluid shear stress intimately regulates vasculogenesis and endothelial homeostasis. The canonical Wnt/β-catenin signaling pathways play an important role in differentiation and proliferation. In this study, we investigated whether shear stress activated angiopoietin-2 (Ang-2) via the canonical Wnt signaling pathway with an implication in vascular endothelial repair. APPROACH AND RESULTS Oscillatory shear stress upregulated both TOPflash Wnt reporter activities and the expression of Ang-2 mRNA and protein in human aortic endothelial cells accompanied by an increase in nuclear β-catenin intensity. Oscillatory shear stress-induced Ang-2 and Axin-2 mRNA expression was downregulated in the presence of a Wnt inhibitor, IWR-1, but was upregulated in the presence of a Wnt agonist, LiCl. Ang-2 expression was further downregulated in response to a Wnt signaling inhibitor, DKK-1, but was upregulated by Wnt agonist Wnt3a. Both DKK-1 and Ang-2 siRNA inhibited endothelial cell migration and tube formation, which were rescued by human recombinant Ang-2. Both Ang-2 and Axin-2 mRNA downregulation was recapitulated in the heat-shock-inducible transgenic Tg(hsp70l:dkk1-GFP) zebrafish embryos at 72 hours post fertilization. Ang-2 morpholino injection of Tg (kdrl:GFP) fish impaired subintestinal vessel formation at 72 hours post fertilization, which was rescued by zebrafish Ang-2 mRNA coinjection. Inhibition of Wnt signaling with IWR-1 also downregulated Ang-2 and Axin-2 expression and impaired vascular repair after tail amputation, which was rescued by zebrafish Ang-2 mRNA injection. CONCLUSIONS Shear stress activated Ang-2 via canonical Wnt signaling in vascular endothelial cells, and Wnt-Ang-2 signaling is recapitulated in zebrafish embryos with a translational implication in vascular development and repair.
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Affiliation(s)
- Rongsong Li
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Tyler Beebe
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Nelson Jen
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Fei Yu
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Wakako Takabe
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Michael Harrison
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Hung Cao
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Juhyun Lee
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Hongbo Yang
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Peidong Han
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Kevin Wang
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Hirohito Shimizu
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Jaunian Chen
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Ching-Ling Lien
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Neil C Chi
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla
| | - Tzung K Hsiai
- From the Department of Medicine, School of Medicine (R.L., T.K.H.), Department of Bioengineering (T.B., N.J., F.Y., W.T., H.C., J.L., T.K.H.), and Department of Molecular, Cell, and Developmental Biology (K.W., H.S., J.C.), University of California, Los Angeles; Department of Surgery, Children's Hospital Los Angeles, CA (M.H., C.-L.L.); and Division of Cardiology, Department of Medicine, School of Medicine (H.Y., P.H., N.C.C.) and Institute of Genomic Medicine (N.C.C.), University of California, San Diego, La Jolla.
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Cao H, Yu F, Zhao Y, Scianmarello N, Lee J, Dai W, Jen N, Beebe T, Li R, Ebrahimi R, Chang DS, Mody FV, Pacella J, Tai YC, Hsiai T. Stretchable electrochemical impedance sensors for intravascular detection of lipid-rich lesions in New Zealand White rabbits. Biosens Bioelectron 2013; 54:610-6. [PMID: 24333932 DOI: 10.1016/j.bios.2013.11.059] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/12/2013] [Accepted: 11/20/2013] [Indexed: 12/31/2022]
Abstract
Flexible electronics have enabled catheter-based intravascular sensing. However, real-time interrogation of unstable plaque remains an unmet clinical challenge. Here, we demonstrate the feasibility of stretchable electrochemical impedance spectroscopy (EIS) sensors for endoluminal investigations in New Zealand White (NZW) rabbits on diet-induced hyperlipidemia. A parylene C (PAC)-based EIS sensor mounted on the surface of an inflatable silicone balloon affixed to the tip of an interrogating catheter was deployed (1) on the explants of NZW rabbit aorta for detection of lipid-rich atherosclerotic lesions, and (2) on live animals for demonstration of balloon inflation and EIS measurements. An input peak-to-peak AC voltage of 10 mV and sweeping-frequency from 300 kHz to 100 Hz were delivered to the endoluminal sites. Balloon inflation allowed EIS sensors to be in contact with endoluminal surface. In the oxidized low-density-lipoprotein (oxLDL)-rich lesions from explants of fat-fed rabbits, impedance magnitude increased significantly by 1.5-fold across the entire frequency band, and phase shifted ~5° at frequencies below 10 kHz. In the lesion-free sites of the normal diet-fed rabbits, impedance magnitude increased by 1.2-fold and phase shifted ~5° at frequencies above 30 kHz. Thus, we demonstrate the feasibility of stretchable intravascular EIS sensors for identification of lipid rich lesions, with a translational implication for detecting unstable lesions.
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Affiliation(s)
- Hung Cao
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Fei Yu
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Yu Zhao
- Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Nick Scianmarello
- Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Juhyun Lee
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Wangde Dai
- The Heart Institute of Good Samaritan Hospital, Los Angeles, CA, United States
| | - Nelson Jen
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Tyler Beebe
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Rongsong Li
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Ramin Ebrahimi
- Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Donald S Chang
- Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - Freny V Mody
- Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States
| | - John Pacella
- Division of Cardiology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Yu-Chong Tai
- Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Tzung Hsiai
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States; Division of Cardiology, Department of Medicine, VA Greater Los Angeles Healthcare System, School of Medicine, University of California, United States.
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Jen N, Yu F, Lee J, Wasmund S, Dai X, Chen C, Chawareeyawong P, Yang Y, Li R, Hamdan MH, Hsiai TK. Atrial fibrillation pacing decreases intravascular shear stress in a New Zealand white rabbit model: implications in endothelial function. Biomech Model Mechanobiol 2013; 12:735-45. [PMID: 22983703 PMCID: PMC3548016 DOI: 10.1007/s10237-012-0437-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 08/29/2012] [Indexed: 01/01/2023]
Abstract
Atrial fibrillation (AF) is characterized by multiple rapid and irregular atrial depolarization, leading to rapid ventricular responses exceeding 100 beats per minute (bpm). We hypothesized that rapid and irregular pacing reduced intravascular shear stress (ISS) with implication to modulating endothelial responses. To simulate AF, we paced the left atrial appendage of New Zealand White rabbits (n = 4) at rapid and irregular intervals. Surface electrical cardiograms were recorded for atrial and ventricular rhythm, and intravascular convective heat transfer was measured by microthermal sensors, from which ISS was inferred. Rapid and irregular pacing decreased arterial systolic and diastolic pressures (baseline, 99/75 mmHg; rapid regular pacing, 92/73; rapid irregular pacing, 90/68; p < 0.001, n = 4), temporal gradients ([Formula: see text] from 1,275 ± 80 to 1,056 ± 180 dyne/cm(2) s), and reduced ISS (from baseline at 32.0 ± 2.4 to 22.7 ± 3.5 dyne/cm(2)). Computational fluid dynamics code demonstrated that experimentally inferred ISS provided a close approximation to the computed wall shear stress at a given catheter to vessel diameter ratio, shear stress range, and catheter position. In an in vitro flow system in which time-averaged shear stress was maintained at [Formula: see text] , we further demonstrated that rapid pulse rates at 150 bpm down-regulated endothelial nitric oxide, promoted superoxide (O 2 (.-) ) production, and increased monocyte binding to endothelial cells. These findings suggest that rapid pacing reduces ISS and [Formula: see text] , and rapid pulse rates modulate endothelial responses.
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Affiliation(s)
- Nelson Jen
- Department of Biomedical Engineering and Cardiovascular Medicine, School of Engineering and Medicine, University of Southern California, Los Angeles, CA 90089, USA
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15
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Jen N, Hsiai T. High-frequency pulsatile shear stress increases mitochondrial DNA damage By JNK activation in endothelial cells. Cardiovasc Pathol 2013. [DOI: 10.1016/j.carpath.2013.01.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Jen N, Li R, Hsiai T. Tachycardia promotes Mitochondrial DNA Damage by JNK Translocation to Mitochondria. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1127.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Yu F, Li R, Jen N, Chi N, Lien C, Hsiai T. Canonical Wnt/ β‐catenin Signaling Pathway mediates Shear Stress‐Activated Angiopoeitin‐2 expression and vasculogenesis. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.526.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Fei Yu
- Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Rongsong Li
- Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Nelson Jen
- Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Neil Chi
- Medicine/CardiologyUniversity of California San DiegoLa JollaCA
| | - Ching‐Ling Lien
- Saban Research InstituteChildren Hospital Los AngelesLos AngelesCA
| | - Tzung Hsiai
- Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
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Yu F, Lee J, Jen N, Li X, Zhang Q, Tang R, Zhou Q, Kim ES, Hsiai TK. Elevated electrochemical impedance in the endoluminal regions with high shear stress: implication for assessing lipid-rich atherosclerotic lesions. Biosens Bioelectron 2012; 43:237-44. [PMID: 23318546 DOI: 10.1016/j.bios.2012.12.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 11/29/2012] [Accepted: 12/04/2012] [Indexed: 12/19/2022]
Abstract
BACKGROUND Identifying metabolically active atherosclerotic lesions remains an unmet clinical challenge during coronary intervention. Electrochemical impedance (EIS) increased in response to oxidized low density lipoprotein (oxLDL)-laden lesions. We hereby assessed whether integrating EIS with intravascular ultrasound (IVUS) and shear stress (ISS) provided a new strategy to assess oxLDL-laden lesions in the fat-fed New Zealand White (NZW) rabbits. METHODS AND RESULTS A micro-heat transfer sensor was deployed to acquire the ISS profiles at baseline and post high-fat diet (HD) in the NZW rabbits (n=8). After 9 weeks of HD, serum oxLDL levels (mg/dL) increased by 140 fold, accompanied by a 1.5-fold increase in kinematic viscosity (cP) in the HD group. Time-averaged ISS (ISSave) in the thoracic aorta also increased in the HD group (baseline: 17.61±0.24 vs. 9 weeks: 25.22±0.95dyne/cm(2), n=4), but remained unchanged in the normal diet group (baseline: 22.85±0.53dyn/cm(2) vs. 9 weeks: 22.37±0.57dyne/cm(2), n=4). High-frequency intravascular ultrasound (IVUS) revealed atherosclerotic lesions in the regions with augmented ISSave, and concentric bipolar microelectrodes demonstrated elevated EIS signals, which were correlated with prominent anti-oxLDL immuno-staining (oxLDL-free regions: 497±55Ω, n=8 vs. oxLDL-rich lesions: 679±125Ω, n=12, P<0.05). The equivalent circuit model for tissue resistance between the lesion-free and ox-LDL-rich lesions further validated the experimental EIS signals. CONCLUSIONS By applying electrochemical impedance in conjunction with shear stress and high-frequency ultrasound sensors, we provided a new strategy to identify oxLDL-laden lesions. The study demonstrated the feasibility of integrating EIS, ISS, and IVUS for a catheter-based approach to assess mechanically unstable plaque.
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Affiliation(s)
- Fei Yu
- Department of Biomedical Engineering and Cardiovascular Medicine, University of Southern California, Los Angeles, CA 90089, USA
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Quigley K, Fang K, Jen N, Li R, Hsiai T. MnSOD reduction causes mtDNA damage in HAEC under Oscillatory Shear Stress. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1134.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Katherine Quigley
- Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Karen Fang
- Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Nelson Jen
- Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Rongsong Li
- Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
| | - Tzung Hsiai
- Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA
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Jen N, Yu F, Lee J, Hsiai T. Flexible sensors to measure intravascular shear stress coupled with rapid and irregular atrial pacing. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1036.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nelson Jen
- University of Southern CaliforniaLos AngelesCA
| | - Fei Yu
- University of Southern CaliforniaLos AngelesCA
| | - Juhyun Lee
- University of Southern CaliforniaLos AngelesCA
| | - Tzung Hsiai
- University of Southern CaliforniaLos AngelesCA
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Li R, Jen N, Yu F, Hsiai TK. Assessing mitochondrial redox status by flow cytometric methods: vascular response to fluid shear stress. Curr Protoc Cytom 2011; Chapter 9:9.37.1-9.37.14. [PMID: 21965108 PMCID: PMC3205925 DOI: 10.1002/0471142956.cy0937s58] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mitochondria are an important source of superoxide production contributing to physiological and pathological responses, including vascular oxidative stress that is relevant to cardiovascular diseases. Vascular oxidative stress is intimately linked with pro-inflammatory states and atherosclerosis. Oxidized low-density lipoprotein (OxLDL) modulates intracellular redox status and induces apoptosis in endothelial cells. Hemodynamic, specifically, fluid shear stress imparts both biomechanical and metabolic effects on vasculature. Mitochondria are an important source of superoxide production contributing to vascular oxidative stress with relevance to cardiovascular diseases. We hereby present biophysical and biochemical approaches, including fluorescence-activated cell sorting, to assess the dynamics of vascular redox status.
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Affiliation(s)
- Rongsong Li
- Cardiovascular Engineering Research, Department of Biomedical Engineering and Cardiology, School of Medicine and School of Engineering, University of Southern California Los Angeles California
| | - Nelson Jen
- Cardiovascular Engineering Research, Department of Biomedical Engineering and Cardiology, School of Medicine and School of Engineering, University of Southern California Los Angeles California
| | - Fei Yu
- Cardiovascular Engineering Research, Department of Biomedical Engineering and Cardiology, School of Medicine and School of Engineering, University of Southern California Los Angeles California
| | - Tzung K. Hsiai
- Cardiovascular Engineering Research, Department of Biomedical Engineering and Cardiology, School of Medicine and School of Engineering, University of Southern California Los Angeles California
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22
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Takabe W, Jen N, Ai L, Hamilton R, Wang S, Holmes K, Dharbandi F, Khalsa B, Bressler S, Barr ML, Li R, Hsiai TK. Oscillatory shear stress induces mitochondrial superoxide production: implication of NADPH oxidase and c-Jun NH2-terminal kinase signaling. Antioxid Redox Signal 2011; 15:1379-88. [PMID: 20919940 PMCID: PMC3144427 DOI: 10.1089/ars.2010.3645] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Fluid shear stress is intimately linked with vascular oxidative stress and atherosclerosis. We posited that atherogenic oscillatory shear stress (OSS) induced mitochondrial superoxide (mtO2•-) production via NADPH oxidase and c-Jun NH(2)-terminal kinase (JNK-1 and JNK-2) signaling. In bovine aortic endothelial cells, OSS (±3 dyn/cm2) induced JNK activation, which peaked at 1 h, accompanied by an increase in fluorescein isothiocyanate-conjugated JNK fluorescent and MitoSOX Red (specific for mtO2•- production) intensities. Pretreatment with apocynin (NADPH oxidase inhibitor) or N-acetyl cysteine (antioxidant) significantly attenuated OSS-induced JNK activation. Apocynin further reduced OSS-mediated dihydroethidium and MitoSOX Red intensities specific for cytosolic O2•- and mtO2•- production, respectively. As a corollary, transfecting bovine aortic endothelial cells with JNK siRNA (siJNK) and pretreating with SP600125 (JNK inhibitor) significantly attenuated OSS-mediated mtO2•- production. Immunohistochemistry on explants of human coronary arteries further revealed prominent phosphorylated JNK staining in OSS-exposed regions. These findings indicate that OSS induces mtO2•- production via NADPH oxidase and JNK activation relevant for vascular oxidative stress.
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Affiliation(s)
- Wakako Takabe
- Department of Biomedical Engineering and Cardiovascular Medicine, University of Southern California, Los Angeles, California 90089, USA
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23
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Jen N, Takabe W, Li R, Ai L, Hsiai TK. Oscillatory fluid shear stress‐induced JNK activation via NADPH oxidase implicates mitochondrial superoxide production in endothelial cells. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.784.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nelson Jen
- Department of Biomedical Engineering and Cardiovascular MedicineUniversity of Southern CaliforniaLos AngelesCA
| | - Wakako Takabe
- Department of Biomedical Engineering and Cardiovascular MedicineUniversity of Southern CaliforniaLos AngelesCA
| | - Rongsong Li
- Department of Biomedical Engineering and Cardiovascular MedicineUniversity of Southern CaliforniaLos AngelesCA
| | - Lisong Ai
- Department of Biomedical Engineering and Cardiovascular MedicineUniversity of Southern CaliforniaLos AngelesCA
| | - Tzung K. Hsiai
- Department of Biomedical Engineering and Cardiovascular MedicineUniversity of Southern CaliforniaLos AngelesCA
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24
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Li R, Ning Z, Majumdar R, Cui J, Takabe W, Jen N, Sioutas C, Hsiai T. Ultrafine particles from diesel vehicle emissions at different driving cycles induce differential vascular pro-inflammatory responses: implication of chemical components and NF-kappaB signaling. Part Fibre Toxicol 2010; 7:6. [PMID: 20307321 PMCID: PMC2859401 DOI: 10.1186/1743-8977-7-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 03/22/2010] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Epidemiological evidence supports the association between exposure to ambient particulate matter (PM) and cardiovascular diseases. Chronic exposure to ultrafine particles (UFP; Dp <100 nm) is reported to promote atherosclerosis in ApoE knockout mice. Atherogenesis-prone factors induce endothelial dysfunction that contributes to the initiation and progression of atherosclerosis. We previously demonstrated that UFP induced oxidative stress via c-Jun N-terminal Kinases (JNK) activation in endothelial cells. In this study, we investigated pro-inflammatory responses of human aortic endothelial cells (HAEC) exposed to UFP emitted from a diesel truck under an idling mode (UFP1) and an urban dynamometer driving schedule (UFP2), respectively. We hypothesize that UFP1 and UFP2 with distinct chemical compositions induce differential pro-inflammatory responses in endothelial cells. RESULTS UFP2 contained a higher level of redox active organic compounds and metals on a per PM mass basis than UFP1. While both UFP1 and UFP2 induced superoxide production and up-regulated stress response genes such as heme oxygenease-1 (HO-1), OKL38, and tissue factor (TF), only UFP2 induced the expression of pro-inflammatory genes such as IL-8 (2.8 +/- 0.3-fold), MCP-1 (3.9 +/- 0.4-fold), and VCAM (6.5 +/- 1.1-fold) (n = 3, P < 0.05). UFP2-exposed HAEC also bound to a higher number of monocytes than UFP1-exposed HAEC (Control = 70 +/- 7.5, UFP1 = 106.7 +/- 12.5, UFP2 = 137.0 +/- 8.0, n = 3, P < 0.05). Adenovirus NF-kappaB Luciferase reporter assays revealed that UFP2, but not UFP1, significantly induced NF-kappaB activities. NF-kappaB inhibitor, CAY10512, significantly abrogated UFP2-induced pro-inflammatory gene expression and monocyte binding. CONCLUSION While UFP1 induced higher level of oxidative stress and stress response gene expression, only UFP2, with higher levels of redox active organic compounds and metals, induced pro-inflammatory responses via NF-kappaB signaling. Thus, UFP with distinct chemical compositions caused differential response patterns in endothelial cells.
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Affiliation(s)
- Rongsong Li
- Biomedical Engineering and Cardiovascular Medicine, USC, Los Angeles, CA 90089, USA
| | - Zhi Ning
- Civil and Environmental Engineering, USC, Los Angeles, CA 90089, USA
| | - Rohit Majumdar
- Biomedical Engineering and Cardiovascular Medicine, USC, Los Angeles, CA 90089, USA
| | - Jeffery Cui
- Civil and Environmental Engineering, USC, Los Angeles, CA 90089, USA
| | - Wakako Takabe
- Biomedical Engineering and Cardiovascular Medicine, USC, Los Angeles, CA 90089, USA
| | - Nelson Jen
- Biomedical Engineering and Cardiovascular Medicine, USC, Los Angeles, CA 90089, USA
| | | | - Tzung Hsiai
- Biomedical Engineering and Cardiovascular Medicine, USC, Los Angeles, CA 90089, USA
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25
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Lee S, Gharavi NM, Honda H, Chang I, Kim B, Jen N, Li R, Zimman A, Berliner JA. A role for NADPH oxidase 4 in the activation of vascular endothelial cells by oxidized phospholipids. Free Radic Biol Med 2009; 47:145-51. [PMID: 19375500 PMCID: PMC2712234 DOI: 10.1016/j.freeradbiomed.2009.04.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2008] [Revised: 03/04/2009] [Accepted: 04/10/2009] [Indexed: 12/31/2022]
Abstract
Previous studies from our group have demonstrated that oxidized 1-palmitoyl-2-arachidonyl-sn-glycerol-3-phosphocholine (Ox-PAPC) activates over 1000 genes in human aortic endothelial cells (HAECs). Prominent among these are genes regulating inflammation, cholesterol homeostasis, antioxidant enzymes, and the unfolded protein response. Previous studies from our lab and others suggested that transcriptional regulation by Ox-PAPC may be controlled, at least in part, by reactive oxygen species. We now present evidence that Ox-PAPC activation of NADPH oxidase 4 (NOX4) is responsible for the regulation of two of these important groups of genes: those controlling inflammation and those involved in sterol regulation. Our data demonstrate that Ox-PAPC increases reactive oxygen species formation in HAECs as seen by DCF fluorescence. NOX4 is the major molecule responsible for this increase because downregulation of NOX4 and its components (p22(phox) and rac1) blocked the Ox-PAPC effect. Our data show that Ox-PAPC did not change NOX4 transcription levels but did induce recruitment of rac1 to the membrane for NOX4 activation. We present evidence that vascular endothelial growth factor receptor 2 (VEGFR2) activation is responsible for rac1 recruitment to the membrane. Finally, we demonstrate that knockdown of NOX4 and its components rac1 and p22(phox) decreases Ox-PAPC induction of inflammatory and sterol regulatory genes, but does not affect Ox-PAPC transcriptional regulation of other genes for antioxidants and the unfolded protein response. In summary, we have identified a VEGFR2/NOX4 regulatory pathway by which Ox-PAPC controls important endothelial functions.
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Affiliation(s)
- Sangderk Lee
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Nima M. Gharavi
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
- Division of Cardiology, Department of Medicine, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Henry Honda
- Division of Cardiology, Department of Medicine, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Irene Chang
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Brandon Kim
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Nelson Jen
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Rongsong Li
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Alejandro Zimman
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
| | - Judith A. Berliner
- Department of Pathology, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
- Division of Cardiology, Department of Medicine, University of California-Los Angeles, 10833 Le Conte Avenue, Los Angeles, California 90095
- Address correspondence and requests for materials to Dr. Judith A. Berliner, MRL 4760, 675, Charles E. Young Dr. S., Los Angeles, CA 90095. Tel.: 310-825-2436. Fax: 310-794-7345. E-mail:
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