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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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Vascular Pathobiology: Atherosclerosis and Large Vessel Disease. Cardiovasc Pathol 2022. [DOI: 10.1016/b978-0-12-822224-9.00006-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Discrepancy between Jun/Fos Proto-Oncogene mRNA and Protein Expression in the Rheumatoid Arthritis Synovial Membrane. J 2020. [DOI: 10.3390/j3020015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rheumatoid arthritis (RA) is a chronic inflammatory and destructive joint disease characterized by overexpression of pro-inflammatory/pro-destructive mediators, whose regulation has been the focus of our previous studies. Since the expression of these proteins commonly depends on AP-1, the expression of the AP-1-forming subunits cJun, JunB, JunD, and cFos was assessed in synovial membrane (SM) samples of RA, osteoarthritis (OA), joint trauma (JT), and normal controls (NC) using ELISA and qRT-PCR. With respect to an observed discrepancy between mRNA and protein levels, the expression of the mRNA stability-modifying factors AU-rich element RNA-binding protein (AUF)-1, tristetraprolin (TTP), and human antigen R (HuR) was measured. JunB and JunD protein expression was significantly higher in RA-SM compared to OA and/or NC. By contrast, jun/fos mRNA expression was significantly (cjun) or numerically decreased (junB, junD, cfos) in RA and OA compared to JT and/or NC. Remarkably, TTP and HuR were also affected by discrepancies between their mRNA and protein levels, since they were significantly decreased at the mRNA level in RA versus NC, but significantly or numerically increased at the protein level when compared to JT and NC. Discrepancies between the mRNA and protein expression for Jun/Fos and TTP/HuR suggest broad alterations of post-transcriptional processes in the RA-SM. In this context, increased levels of mRNA-destabilizing TTP may contribute to the low levels of jun/fos and ttp/hur mRNA, whereas abundant mRNA-stabilizing HuR may augment translation of the remaining mRNA into protein with potential consequences for the composition of the resulting AP-1 complexes and the expression of AP-1-dependent genes in RA.
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Mechanosensing in liver regeneration. Semin Cell Dev Biol 2017; 71:153-167. [DOI: 10.1016/j.semcdb.2017.07.041] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 07/25/2017] [Accepted: 07/26/2017] [Indexed: 12/13/2022]
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Kim J, Montagne K, Nemoto H, Ushida T, Furukawa KS. Hypergravity down-regulates c-fos gene expression via ROCK/Rho-GTP and the PI3K signaling pathway in murine ATDC5 chondroprogenitor cells. PLoS One 2017; 12:e0185394. [PMID: 28953959 PMCID: PMC5617206 DOI: 10.1371/journal.pone.0185394] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022] Open
Abstract
Chondrocytes are known to be physiologically loaded with diverse physical factors such as compressive stress, shear stress and hydrostatic pressure. Although the effects of those mechanical stimuli onto various cell models have been widely studied, those of hypergravity have not yet been revealed clearly. Hereby, we hypothesized that the hypergravity affects relative positions of intracellular elements including nucleus and cytoskeletons due to their density differences, triggering mechanotransduction in the cell. The aim of this study was to investigate the effect of hypergravity on c-fos expression in the murine ATDC5 chondroprogenitor cells, as c-fos is a well known key regulator of cell proliferation and differentiation, including in chondrocytes. We first found that hypergravity down-regulated c-fos expression transiently via ROCK/Rho-GTP and PI3K signaling, and the down-regulation was suppressed by inhibition of actin polymerization.
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Affiliation(s)
- Jeonghyun Kim
- Department of Mechanical Engineering, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
| | - Kevin Montagne
- Department of Mechanical Engineering, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
| | - Hidetoshi Nemoto
- Division of Regenerative Medical Engineering, Center for Disease Biology and Integrative Medicine, School of Medicine, University of Tokyo, Tokyo, Japan
| | - Takashi Ushida
- Department of Mechanical Engineering, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
| | - Katsuko S. Furukawa
- Department of Mechanical Engineering, Graduate School of Engineering, University of Tokyo, Tokyo, Japan
- Department of Bioengineering, Graduate school of engineering, University of Tokyo, Tokyo, Japan
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Xu JX, Xiong W, Zeng Z, Tang Y, Wang YL, Xiao M, Li M, Li QS, Song GL, Kuang J. Effect of ART1 on the proliferation and migration of mouse colon carcinoma CT26 cells in vivo. Mol Med Rep 2017; 15:1222-1228. [PMID: 28138708 PMCID: PMC5367323 DOI: 10.3892/mmr.2017.6152] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 11/17/2016] [Indexed: 01/11/2023] Open
Abstract
Arginine-specific mono-ADP-ribosyltransferase 1 (ART1) is an important enzyme that catalyzes arginine-specific mono-ADP-ribosylation. There is evidence that arginine-specific mono-ADP-ribosylation may affect the proliferation of smooth muscle cells via the Rho-dependent signaling pathway. Previous studies have demonstrated that ART1 may have a role in the proliferation, invasion and apoptosis of colon carcinoma in vitro. However, the effect of ART1 on the proliferation and invasion of colon carcinoma in vivo has yet to be elucidated. In the present study, mouse colon carcinoma CT26 cells were infected with a lentivirus to produce ART1 gene silencing or overexpression, and were then subcutaneously transplanted. To observe the effect of ART1 on tumor growth or liver metastasis in vivo, a spleen transplant tumor model of CT26 cells in BALB/c mice was successfully constructed. Expression levels of focal adhesion kinase (FAK), Ras homolog gene family member A (RhoA) and the downstream factors, c-myc, c-fos and cyclooxygenase-2 (COX-2) proteins, were measured in vivo. The results demonstrated that ART1 gene silencing inhibited the growth of the spleen transplanted tumor and its ability to spread to the liver via metastasis. There was also an accompanying increase in expression of FAK, RhoA, c-myc, c-fos and COX-2, whereas CT26 cells with ART1 overexpression demonstrated the opposite effect. These results suggest a potential role for ART1 in the proliferation and invasion of CT26 cells and a possible mechanism in vivo.
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Affiliation(s)
- Jian-Xia Xu
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Wei Xiong
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Zhen Zeng
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Yi Tang
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Ya-Lan Wang
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Ming Xiao
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Ming Li
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Qing Shu Li
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Guang-Lin Song
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
| | - Jing Kuang
- Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, P.R. China
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8
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Loomis SJ, Kang JH, Weinreb RN, Yaspan BL, Cooke Bailey JN, Gaasterland D, Gaasterland T, Lee RK, Lichter PR, Budenz DL, Liu Y, Realini T, Friedman DS, McCarty CA, Moroi SE, Olson L, Schuman JS, Singh K, Vollrath D, Wollstein G, Zack DJ, Brilliant M, Sit AJ, Christen WG, Fingert J, Kraft P, Zhang K, Allingham RR, Pericak-Vance MA, Richards JE, Hauser MA, Haines JL, Pasquale LR, Wiggs JL. Association of CAV1/CAV2 genomic variants with primary open-angle glaucoma overall and by gender and pattern of visual field loss. Ophthalmology 2014; 121:508-16. [PMID: 24572674 PMCID: PMC3937766 DOI: 10.1016/j.ophtha.2013.09.012] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 09/04/2013] [Accepted: 09/08/2013] [Indexed: 10/26/2022] Open
Abstract
PURPOSE The CAV1/CAV2 (caveolin 1 and caveolin 2) genomic region previously was associated with primary open-angle glaucoma (POAG), although replication among independent studies has been variable. The aim of this study was to assess the association between CAV1/CAV2 single nucleotide polymorphisms (SNPs) and POAG in a large case-control dataset and to explore associations by gender and pattern of visual field (VF) loss further. DESIGN Case-control study. PARTICIPANTS We analyzed 2 large POAG data sets: the Glaucoma Genes and Environment (GLAUGEN) study (976 cases, 1140 controls) and the National Eye Institute Glaucoma Human Genetics Collaboration (NEIGHBOR) consortium (2132 cases, 2290 controls). METHODS We studied the association between 70 SNPs located within the CAV1/CAV2 genomic region in the GLAUGEN and NEIGHBOR studies, both genotyped on the Illumina Human 660WQuadv1C BeadChip array and imputed with the Markov Chain Haplotyping algorithm using the HapMap 3 reference panel. We used logistic regression models of POAG in the overall population and separated by gender, as well as by POAG subtypes defined by type of VF defect (peripheral or paracentral). Results from GLAUGEN and NEIGHBOR were meta-analyzed, and a Bonferroni-corrected significance level of 7.7 × 10(-4) was used to account for multiple comparisons. MAIN OUTCOME MEASURES Overall POAG, overall POAG by gender, and POAG subtypes defined by pattern of early VF loss. RESULTS We found significant associations between 10 CAV1/CAV2 SNPs and POAG (top SNP, rs4236601; pooled P = 2.61 × 10(-7)). Of these, 9 were significant only in women (top SNP, rs4236601; pooled P = 1.59 × 10(-5)). Five of the 10 CAV1/CAV2 SNPs were associated with POAG with early paracentral VF (top SNP, rs17588172; pooled P = 1.07 × 10(-4)), and none of the 10 were associated with POAG with peripheral VF loss only or POAG among men. CONCLUSIONS CAV1/CAV2 SNPs were associated significantly with POAG overall, particularly among women. Furthermore, we found an association between CAV1/CAV2 SNPs and POAG with paracentral VF defects. These data support a role for caveolin 1, caveolin 2, or both in POAG and suggest that the caveolins particularly may affect POAG pathogenesis in women and in patients with early paracentral VF defects.
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Affiliation(s)
- Stephanie J Loomis
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts
| | - Jae H Kang
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Robert N Weinreb
- Department of Ophthalmology and Hamilton Glaucoma Center, University of California, San Diego, La Jolla, California
| | | | - Jessica N Cooke Bailey
- Center for Human Genetics Research, Vanderbilt University School of Medicine, Nashville, Tennessee
| | | | - Terry Gaasterland
- Scripps Genome Center, University of California at San Diego, La Jolla, California
| | - Richard K Lee
- Bascom Palmer Eye Institute and Human Genomics, University of Miami Miller School of Medicine, Miami, Florida
| | - Paul R Lichter
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Donald L Budenz
- Department of Ophthalmology, University of North Carolina, Chapel Hill, North Carolina
| | - Yutao Liu
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina; Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Tony Realini
- Department of Ophthalmology, West Virginia University Eye Institute, Morgantown, West Virginia
| | - David S Friedman
- Wilmer Eye Institute, Johns Hopkins University Hospital, Baltimore, Maryland
| | | | - Sayoko E Moroi
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Lana Olson
- Center for Human Genetics Research, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Joel S Schuman
- Department of Ophthalmology, UPMC Eye Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kuldev Singh
- Department of Ophthalmology, Stanford University, Palo Alto, California
| | - Douglas Vollrath
- Department of Genetics, Stanford University, Palo Alto, California
| | - Gadi Wollstein
- Department of Ophthalmology, UPMC Eye Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Donald J Zack
- Wilmer Eye Institute, Johns Hopkins University Hospital, Baltimore, Maryland
| | - Murray Brilliant
- Center for Human Genetics, Marshfield Clinic Research Foundation, Marshfield, Wisconsin
| | - Arthur J Sit
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota
| | - William G Christen
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - John Fingert
- Departments of Ophthalmology and Anatomy/Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Peter Kraft
- Departments of Epidemiology and Biostatistics, Harvard School of Public Health, Harvard University, Boston, Massachusetts
| | - Kang Zhang
- Department of Ophthalmology and Hamilton Glaucoma Center, University of California, San Diego, La Jolla, California
| | - R Rand Allingham
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Margaret A Pericak-Vance
- Bascom Palmer Eye Institute and Human Genomics, University of Miami Miller School of Medicine, Miami, Florida
| | - Julia E Richards
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Michael A Hauser
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina; Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Jonathan L Haines
- Center for Human Genetics Research, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Louis R Pasquale
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts; Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Janey L Wiggs
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts.
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Johnson BD, Mather KJ, Wallace JP. Mechanotransduction of shear in the endothelium: basic studies and clinical implications. Vasc Med 2012; 16:365-77. [PMID: 22003002 DOI: 10.1177/1358863x11422109] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The endothelium plays an integral role in the development and progression of atherosclerosis. Hemodynamic forces, particularly shear stress, have a powerful influence on endothelial phenotype and function; however, there is no clear consensus on how endothelial cells sense shear. Nevertheless, multiple endothelial cell signal transduction pathways are activated when exposed to shear stress in vitro. The type of shear, laminar or oscillatory, impacts which signal transduction pathways are initiated as well as which subsequent genes are up- or down-regulated, thereby influencing endothelial phenotype and function. Recently, human studies have examined the impact of shear stress and different shear patterns at rest and during exercise on endothelial function. Current evidence supports the theory that augmented exercise-induced shear stress contributes to improved endothelial function following acute exercise and exercise training, whereas retrograde shear initiates vascular dysfunction. The purpose of this review is to examine the current theories on how endothelial cells sense shear stress, to provide an overview on shear stress-induced signal transduction pathways and subsequent gene expression, and to review the current literature pertaining to shear stress and shear patterns at rest as well as during exercise in humans and the related effects on endothelial function.
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Qian T, Wang Y. Micro/nano-fabrication technologies for cell biology. Med Biol Eng Comput 2010; 48:1023-32. [PMID: 20490938 PMCID: PMC3373892 DOI: 10.1007/s11517-010-0632-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 04/21/2010] [Indexed: 10/19/2022]
Abstract
Micro/nano-fabrication techniques, such as soft lithography and electrospinning, have been well-developed and widely applied in many research fields in the past decade. Due to the low costs and simple procedures, these techniques have become important and popular for biological studies. In this review, we focus on the studies integrating micro/nano-fabrication work to elucidate the molecular mechanism of signaling transduction in cell biology. We first describe different micro/nano-fabrication technologies, including techniques generating three-dimensional scaffolds for tissue engineering. We then introduce the application of these technologies in manipulating the physical or chemical micro/nano-environment to regulate the cellular behavior and response, such as cell life and death, differentiation, proliferation, and cell migration. Recent advancement in integrating the micro/nano-technologies and live cell imaging are also discussed. Finally, potential schemes in cell biology involving micro/nano-fabrication technologies are proposed to provide perspectives on the future research activities.
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Affiliation(s)
- Tongcheng Qian
- Department of Bioengineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Biomedical Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Yingxiao Wang
- Department of Bioengineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA, Department of Integrative and Molecular Physiology, Center for Biophysics and Computational Biology, Institute for Genomic, Biology, Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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Dahl KN, Kalinowski A, Pekkan K. Mechanobiology and the microcirculation: cellular, nuclear and fluid mechanics. Microcirculation 2010; 17:179-91. [PMID: 20374482 DOI: 10.1111/j.1549-8719.2009.00016.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Endothelial cells are stimulated by shear stress throughout the vasculature and respond with changes in gene expression and by morphological reorganization. Mechanical sensors of the cell are varied and include cell surface sensors that activate intracellular chemical signaling pathways. Here, possible mechanical sensors of the cell including reorganization of the cytoskeleton and the nucleus are discussed in relation to shear flow. A mutation in the nuclear structural protein lamin A, related to Hutchinson-Gilford progeria syndrome, is reviewed specifically as the mutation results in altered nuclear structure and stiffer nuclei; animal models also suggest significantly altered vascular structure. Nuclear and cellular deformation of endothelial cells in response to shear stress provides partial understanding of possible mechanical regulation in the microcirculation. Increasing sophistication of fluid flow simulations inside the vessel is also an emerging area relevant to the microcirculation as visualization in situ is difficult. This integrated approach to study--including medicine, molecular and cell biology, biophysics and engineering--provides a unique understanding of multi-scale interactions in the microcirculation.
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Affiliation(s)
- Kris Noel Dahl
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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Wang XL, Fu A, Spiro C, Lee HC. Proteomic Analysis of Vascular Endothelial Cells-Effects of Laminar Shear Stress and High Glucose. ACTA ACUST UNITED AC 2009; 2:445. [PMID: 20148124 DOI: 10.4172/jpb.1000104] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study directly measured the relative protein levels in bovine aortic endothelial cells (BAEC) that were cultured for two weeks in normal (5 mM, NG) or high (22 mM, HG) glucose and then were subjected to laminar shear stress at 0 or 15 dynes/cm(2). Membrane preparations were labeled with one of the four isobaric tagging reagents (iTRAQ), followed by LC-MS/MS analysis. The results showed that HG and/or shear stress induced alterations in various membrane associated proteins involving many signaling pathways. While shear stress induced an increase in heat shock proteins and protein ubiquitination, which remained enhanced in HG, the effects of shear stress on the mechanosensing and protein phosphorylation pathways were altered by HG. These results were validated by Western blot analysis, suggesting that HG importantly modulates shear stress-mediated endothelial function.
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Affiliation(s)
- Xiao-Li Wang
- Departments of Internal Medicine, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA
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Silbert O, Wang Y, Maciejewski BS, Lee H, Shaw SK, Sanchez–Esteban J. ROLES OF RhoA AND Rac1 ON ACTIN REMODELING AND CELL ALIGNMENT AND DIFFERENTIATION IN FETAL TYPE II EPITHELIAL CELLS EXPOSED TO CYCLIC MECHANICAL STRETCH. Exp Lung Res 2009; 34:663-80. [DOI: 10.1080/01902140802339615] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
The compliance of the extracellular matrix (ECM) regulates osteogenic differentiation by modulating extracellular signal-regulated kinase (ERK) activity. However, the molecular mechanism linking ECM compliance to the ERK-mitogen-activated protein kinase (MAPK) pathway remains unclear. Furthermore, RhoA has been widely implicated in integrin-mediated signaling and mechanotransduction. We studied the relationship between RhoA and ERK-MAPK signaling to determine their roles in the regulation of osteogenesis by ECM compliance. Inhibition of RhoA and ROCK in MC3T3-E1 pre-osteoblasts cultured on substrates of varying compliance reduced ERK activity, whereas constitutively active RhoA enhanced it. The expression of RUNX2, a potent osteogenic transcription factor, was increased on stiffer matrices and correlated with elevated ERK activity. Inhibition of RhoA, ROCK, or the MAPK pathway diminished RUNX2 activity and delayed the onset of osteogenesis as shown by altered osteocalcin (OCN) and bone sialoprotein (BSP) gene expression, alkaline phosphatase (ALP) activity, and matrix mineralization. These data establish that one possible mechanism by which ECM rigidity regulates osteogenic differentiation involves MAPK activation downstream of the RhoA-ROCK signaling pathway.
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Mammoto A, Mammoto T, Ingber DE. Rho signaling and mechanical control of vascular development. Curr Opin Hematol 2008; 15:228-34. [PMID: 18391790 DOI: 10.1097/moh.0b013e3282fa7445] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE OF REVIEW To discuss how mechanical cues and Rho signaling contribute to control of vascular development and hematopoiesis. RECENT FINDINGS Rho guanine trinucleotide phosphatases are ubiquitious regulators of cytoskeletal structure and tension generation. Recent work shows that Rho-dependent mechanical interactions between cells and extracellular matrix regulate cell fate switching in capillary endothelial cells and megakaryocytes in vitro, as well as angiogenesis, vascular permeability, leukocyte migration and platelet formation in vivo. Signaling pathways that link integrins and tension-dependent changes in cytoskeletal structure to Rho have also begun to be delineated. SUMMARY Mechanical force generation by cells and simultaneous sensing of these physical forces play critical roles in vascular development by estimating whether individual cells will grow, differentiate, move or undergo apoptosis in the local tissue microenvironment. Future work in the vascular field therefore needs to incorporate physical control mechanisms into existing biochemical concepts of cell and tissue regulation.
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Affiliation(s)
- Akiko Mammoto
- Vascular Biology Program, Department of Pathology, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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Kumai T, Takeba Y, Matsumoto N, Nakaya S, Tsuzuki Y, Yanagida Y, Hayashi M, Kobayashi S. Fasudil attenuates sympathetic nervous activity in the adrenal medulla of spontaneously hypertensive rats. Life Sci 2007; 81:1193-8. [PMID: 17889905 DOI: 10.1016/j.lfs.2007.08.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Revised: 07/24/2007] [Accepted: 08/06/2007] [Indexed: 01/01/2023]
Abstract
We investigated the effects of fasudil, a Rho kinase inhibitor, on hypertension in spontaneously hypertensive rats and on the catecholamine synthetic pathway. Ten-week-old male SHR and Wistar-Kyoto rats were administered fasudil (10 mg/kg/day s.c.) for 4 days. Systolic blood pressure was measured using the tail-cuff method. Catecholamine levels were measured with high-performance liquid chromatography-ECD methods. Tyrosine hydroxylase protein levels were measured in Western blot analysis. The tyrosine hydroxylase mRNA level was measured using real-time PCR methods. Fasudil significantly decreased systolic blood pressure in spontaneously hypertensive rats, but not in Wistar-Kyoto rats. Fasudil also significantly decreased catecholamine, tyrosine hydroxylase protein, and tyrosine hydroxylase mRNA levels in the adrenal medulla of spontaneously hypertensive rats. These results suggest that the depressor effects of fasudil on hypertension in spontaneously hypertensive rats may be related to inhibition of the catecholamine synthetic pathway.
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Affiliation(s)
- Toshio Kumai
- Department of Pharmacology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki 2168511, Japan.
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Cicha I, Goppelt-Struebe M, Muehlich S, Yilmaz A, Raaz D, Daniel WG, Garlichs CD. Pharmacological inhibition of RhoA signaling prevents connective tissue growth factor induction in endothelial cells exposed to non-uniform shear stress. Atherosclerosis 2007; 196:136-145. [PMID: 17452038 DOI: 10.1016/j.atherosclerosis.2007.03.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Revised: 03/05/2007] [Accepted: 03/08/2007] [Indexed: 01/30/2023]
Abstract
Shear stress changes play an important role in atheroma formation. This study focussed on atherogenic protein expression under non-uniform shear stress and the pharmacological modulation of shear-related endothelial dysfunction. Bifurcating flow-through cell culture slides were used to expose HUVECs to steady laminar or non-uniform shear stress for 18 h at 10 dyn/cm(2). Protein expression was determined by immunofluorescence, and quantified using MetaVue software. Laminar shear stress resulted in cell alignment, reduced F-actin fibers, and significant induction of endothelial nitric oxide synthase expression. Under non-uniform shear stress at bifurcations, minor upregulation of adhesion molecules was observed. Connective tissue growth factor (CTGF) was significantly downregulated by laminar shear stress and induced in cells exposed to non-uniform shear stress. CTGF upregulation by non-uniform shear stress was RhoA-dependent, because it was almost completely inhibited in cells transfected with dominant negative RhoA-N19, and when cells were treated with 1 micromol/L simvastatin during flow. Pre-incubation of HUVECs with inhibitors of Rho-associated kinase before exposure to flow significantly suppressed the CTGF induction in regions of non-uniform shear stress. In conclusion, non-uniform shear stress-dependent CTGF expression requires active RhoA and can be prevented pharmacologically. Interference with shear stress-induced protein expression may inhibit endothelial dysfunction in atheroprone vessel regions.
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Affiliation(s)
- Iwona Cicha
- Medical Clinic 2, University of Erlangen-Nuremberg, Erlangen, Germany.
| | | | - Susanne Muehlich
- Medical Clinic 4, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Atilla Yilmaz
- Medical Clinic 2, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Dorette Raaz
- Medical Clinic 2, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Werner G Daniel
- Medical Clinic 2, University of Erlangen-Nuremberg, Erlangen, Germany
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18
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Wang XL, Fu A, Raghavakaimal S, Lee HC. Proteomic analysis of vascular endothelial cells in response to laminar shear stress. Proteomics 2007; 7:588-596. [PMID: 17309104 DOI: 10.1002/pmic.200600568] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Isotope-coded affinity tags (cICAT) coupled with mass spectrometric analysis is one of the leading technologies for quantitative proteomic profiling and protein quantification. We performed proteomic analysis of bovine aortic endothelial cells (BAEC) in response to laminar shear stress using cICAT labeling coupled with LC-MS/MS. Protein expressions in BAEC under 15 dynes/cm2 of shear stress for 10 min, 3 h, and 6 h were compared with matched stationary controls. Analysis of each sample produced 1800-2400 proteins at >or=75% confidence level. We found 142, 213, and 186 candidate proteins that were up- or down-regulated by at least two-fold after 10 min, 3 h, and 6 h of shear stress, respectively. Some of these proteins have known cellular functions and they encompass many signaling pathways. The signaling pathways that respond to shear stress include those of integrins, G-protein-coupled receptors, glutamate receptors, PI3K/AKT, apoptosis, Notch and cAMP-mediated signaling pathways. The validity of the mass spectrometric analysis was also confirmed by Western blot and confocal immunofluorescence microscopy. The present quantitative proteomic analysis suggests novel potential regulatory mechanisms in vascular endothelial cells in response to shear stress. These results provide preliminary footprints for further studies on the signaling mechanisms induced by shear stress.
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Affiliation(s)
- Xiao-Li Wang
- Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
| | - Alex Fu
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | | | - Hon-Chi Lee
- Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
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19
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Abstract
Fluid shear stress caused by blood flow is a major determinant of vascular remodeling and arterial tone and can lead to development of atherosclerosis. The endothelial monolayer in vivo acts as a signal transduction interface for hemodynamic forces; these forces determine the shape, cytoskeletal organization, and function of endothelial cells, allowing the vessels to cope with physiological or pathological conditions. The Ras superfamily of GTPases have been revealed to be master regulators of many cellular activities. In particular, the GTPases RhoA, Rac1, and Cdc42 are known to regulate cell shape changes through effects on the cytoskeleton, but their ability to influence polarity, microtubule dynamics, and transcription factor activity is just as significant. Shear stress modulates the activity of small GTPases, which are critical for both cytoskeletal reorganization and changes in gene expression in response to shear stress. The goal of this article is to review what is known about Ras and more so about Rho GTPases in mechanotransduction and the responses of cells to fluid flow. Several distinct signaling pathways can be coordinately activated by flow, and small GTPases are strongly implicated in some of them; thus possible connections will be explored and a unifying hypothesis offered.
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Affiliation(s)
- Eleni Tzima
- Department of Cell and Molecular Physiology, Carolina Cardiovascular Biology Center, University of North Carolina, Chapel Hill, NC 27599, USA.
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20
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Joung IS, Iwamoto MN, Shiu YT, Quam CT. Cyclic strain modulates tubulogenesis of endothelial cells in a 3D tissue culture model. Microvasc Res 2005; 71:1-11. [PMID: 16368114 DOI: 10.1016/j.mvr.2005.10.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 10/07/2005] [Accepted: 10/16/2005] [Indexed: 12/23/2022]
Abstract
Angiogenesis is the formation of new blood vessels from preexisting capillaries or venules. It occurs in a mechanically dynamic environment due to blood flow, but the role of hemodynamic forces in angiogenesis remains poorly understood. We have developed a unique in vitro system for the investigation of angiogenesis under cyclic strain. In this system, tubulogenesis of vascular endothelial cells in 3D collagen gels occurs under well-defined cyclic strain, which mimics blood-pressure-induced stretch. Using this system, we demonstrate that cyclic strain results in alignment of endothelial-cord-like structures perpendicular to the principal axis of stretch. Such preferential orientation was the most evident in deep and long cord-like structures. This in vitro system, along with the novel findings of strain-modulated endothelial tube morphology, enables the formation of an experimental basis for understanding the role of cyclic strain in the regulation of angiogenesis.
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Affiliation(s)
- In Suk Joung
- Department of Bioengineering, University of Utah, 20 South 2030 East, BPR Room 506, Salt Lake City, 84112, USA
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21
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Abstract
The migration of endothelial cells (ECs) plays an important role in vascular remodeling and regeneration. EC migration can be regulated by different mechanisms such as chemotaxis, haptotaxis, and mechanotaxis. This review will focus on fluid shear stress-induced mechanotransduction during EC migration. EC migration and mechanotransduction can be modulated by cytoskeleton, cell surface receptors such as integrins and proteoglycans, the chemical and physical properties of extracellular matrix (ECM) and cell-cell adhesions. The shear stress applied on the luminal surface of ECs can be sensed by cell membrane and associated receptor and transmitted throughout the cell to cell-ECM adhesions and cell-cell adhesions. As a result, shear stress induces directional migration of ECs by promoting lamellipodial protrusion and the formation of focal adhesions (FAs) at the front in the flow direction and the disassembly of FAs at the rear. Persistent EC migration in the flow direction can be driven by polarized activation of signaling molecules and the positive feedback loops constituted by Rho GTPases, cytoskeleton, and FAs at the leading edge. Furthermore, shear stress-induced EC migration can overcome the haptotaxis of ECs. Given the hemodynamic environment of the vascular system, mechanotransduction during EC migration has a significant impact on vascular development, angiogenesis, and vascular wound healing.
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Affiliation(s)
- Song Li
- Department of Bioengineering and Center for Functional Tissue Engineering, University of California-Berkeley, San Francisco/Berkeley, California 94720, USA.
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22
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Li YSJ, Haga JH, Chien S. Molecular basis of the effects of shear stress on vascular endothelial cells. J Biomech 2005; 38:1949-71. [PMID: 16084198 DOI: 10.1016/j.jbiomech.2004.09.030] [Citation(s) in RCA: 589] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Accepted: 09/20/2004] [Indexed: 12/15/2022]
Abstract
Blood vessels are constantly exposed to hemodynamic forces in the form of cyclic stretch and shear stress due to the pulsatile nature of blood pressure and flow. Endothelial cells (ECs) are subjected to the shear stress resulting from blood flow and are able to convert mechanical stimuli into intracellular signals that affect cellular functions, e.g., proliferation, apoptosis, migration, permeability, and remodeling, as well as gene expression. The ECs use multiple sensing mechanisms to detect changes in mechanical forces, leading to the activation of signaling networks. The cytoskeleton provides a structural framework for the EC to transmit mechanical forces between its luminal, abluminal and junctional surfaces and its interior, including the cytoplasm, the nucleus, and focal adhesion sites. Endothelial cells also respond differently to different modes of shear forces, e.g., laminar, disturbed, or oscillatory flows. In vitro studies on cultured ECs in flow channels have been conducted to investigate the molecular mechanisms by which cells convert the mechanical input into biochemical events, which eventually lead to functional responses. The knowledge gained on mechano-transduction, with verifications under in vivo conditions, will advance our understanding of the physiological and pathological processes in vascular remodeling and adaptation in health and disease.
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Affiliation(s)
- Yi-Shuan J Li
- Department of Bioengineering, University of California, San Diego, La Jolla, 92093-0412, USA
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23
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Abstract
Cell motility is an essential cellular process for a variety of biological events. The process of cell migration requires the integration and coordination of complex biochemical and biomechanical signals. The protrusion force at the leading edge of a cell is generated by the cytoskeleton, and this force generation is controlled by multiple signaling cascades. The formation of new adhesions at the front and the release of adhesions at the rear involve the outside-in and inside-out signaling mediated by integrins and other adhesion receptors. The traction force generated by the cell on the extracellular matrix (ECM) regulates cell-ECM adhesions, and the counter force exerted by ECM on the cell drives the migration. The polarity of cell migration can be amplified and maintained by the feedback loop between the cytoskeleton and cell-ECM adhesions. Cell migration in three-dimensional ECM has characteristics distinct from that on two-dimensional ECM. The migration of cells is initiated and modulated by external chemical and mechanical factors, such as chemoattractants and the mechanical forces acting on the cells and ECM, as well as the surface density, distribution, topography, and rigidity of the ECM.
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Affiliation(s)
- Song Li
- Department of Bioengineering and Center for Tissue Engineering, University of California, Berkeley, CA 94720, USA
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24
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Hashimoto K, Parker A, Malone P, Gabelt BT, Rasmussen C, Kaufman PS, Hernandez MR. Long-term activation of c-Fos and c-Jun in optic nerve head astrocytes in experimental ocular hypertension in monkeys and after exposure to elevated pressure in vitro. Brain Res 2005; 1054:103-15. [PMID: 16081055 DOI: 10.1016/j.brainres.2005.06.050] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Revised: 06/10/2005] [Accepted: 06/14/2005] [Indexed: 11/30/2022]
Abstract
This study investigates whether the immediate early gene (IEG) products c-Fos and c-Jun are activated in vivo in monkeys with experimental glaucoma, and in vitro in cultured human ONH astrocytes exposed to hydrostatic pressure (HP). Three Rhesus monkeys with mild glaucomatous damage (mean intraocular pressure (IOP) 27 +/- 1.3 mm Hg approximately 42 weeks) and three with moderate glaucomatous damage (mean IOP 44 +/- 6.7% mm Hg approximately 11 weeks) were used for this study; the contralateral eye served as normal control (mean IOP 18.6 +/- 1.7 mm Hg). ONH tissues were stained with GFAP, DAPI, and c-Jun or c-Fos, and transcription factor positive and negative nuclei were counted to determine nuclear localization. Cultured human normal and glaucomatous ONH astrocytes exposed to elevated HP served as the in vitro model of elevated pressure. Activation and nuclear localization of c-Fos and c-Jun increased significantly in the monkeys with elevated IOP. These data correlated with axonal loss, reactive astrocytes, and remodeling of the optic disc. Cultured human ONH astrocytes showed increased nuclear localization of c-Fos and c-Jun under exposure to HP. Immunohistochemistry demonstrated that the upstream regulators of c-Fos and c-Jun, ERK-MAPK and MAPKp38 localized to the nuclei of ONH astrocytes in monkeys with experimental glaucoma. Taken together, these results demonstrate c-Fos and c-Jun activation in ONH astrocytes in vivo and in vitro, and that activation of both transcription factors is associated with ERK and MAPKp38 activation in experimental glaucoma, suggesting that activation of transcription factors may participate in the induction and maintenance of the reactive astrocyte phenotype in glaucomatous optic neuropathy.
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Affiliation(s)
- K Hashimoto
- Division of Ophthalmology and Visual Science, Niigata University Graduate School, 1-757 Asahimachi, Niigata 951-8510, Japan
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25
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Wang J, Laschinger C, Zhao XH, Mak B, Seth A, McCulloch CA. Mechanical force activates eIF-2α phospho-kinases in fibroblast. Biochem Biophys Res Commun 2005; 330:123-30. [PMID: 15781241 DOI: 10.1016/j.bbrc.2005.02.140] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Indexed: 10/25/2022]
Abstract
Mechanical forces can induce differentiation of fibroblasts into myofibroblasts, a process which requires activation of the MAP kinase p38. Currently, the identification of other phospho-kinases involved in myofibroblast differentiation has not been explored. We applied static tensile forces to rat cardiac fibroblasts via collagen-coated magnetite beads and examined activation of protein phospho-kinases by the Kinexus phospho-antibody screening system. Of 75 candidate protein kinases screened, 39 were detected and, of these, 31 phospho-kinases were analyzed. Following force application, 12 out of 31 phospho-kinases exhibited increases of phosphorylation including PKR (>4-fold), MKK3 (3-fold), MKK6 ( approximately 2-fold), and p38 ( approximately 2-fold). In several types of mechanically sensitive, contractile fibroblasts including rat cardiac, human gingival, and Rat-2 fibroblasts, tensile forces increased eIF-2alpha phosphorylation, a downstream effector of PKR. We conclude that phospho-antibody screening is an efficient method for discovery of novel mechanical force-induced phospho-kinases and force can activate eIF-2alpha phospho-kinases in fibroblasts.
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Affiliation(s)
- J Wang
- CIHR Group in Matrix Dynamics, Faculty of Dentistry, University of Toronto, Toronto, Ont., Canada
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26
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Kalra N, Kumar V. c-Fos is a mediator of the c-myc-induced apoptotic signaling in serum-deprived hepatoma cells via the p38 mitogen-activated protein kinase pathway. J Biol Chem 2004; 279:25313-9. [PMID: 15078869 DOI: 10.1074/jbc.m400932200] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The proto-oncogene c-myc encodes a transcription factor that plays a pivotal role in cell proliferation, differentiation, and apoptosis. The signaling mechanism of c-Myc-induced apoptosis was investigated on the human hepatoma Huh7 cells under growth factor-deprived conditions. The apoptotic process did not involve p53. Rather it was dependent on the expression of c-Fos. Activation of caspases 3 and 9 and down-regulation of Bcl2 were observed in the apoptotic process, indicating it to be a mitochondria-dependent event. An increase in the p38 mitogen-activated protein kinase that was mediated by a Rac1-dependent and cdc42-independent pathway eventually leading to up-regulation of c-Fos activity was also observed. Deletion analysis of the promoter region of the c-fos gene indicated that the ATF2-responsive element conferred the Myc-induced expression of c-Fos. Co-expression of the dominant-negative mutants of c-Fos, p38, and Rac1 blocked the Myc-mediated apoptosis. SB20358, a chemical inhibitor of p38 pathway, also specifically blocked the apoptotic signaling by c-Myc. Furthermore, co-expression of the hepatitis B virus X protein (HBx) along with Myc abrogated the apoptotic signals. The HBx expression was associated with an increase in the levels of phosphorylated AKT and down-regulation of c-Fos by Myc. Thus, c-Fos seems be a new mediator of c-Myc-induced apoptosis.
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Affiliation(s)
- Neetu Kalra
- Virology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
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