Integrins Expressed With Bladder Extracellular Matrix After Stretch Injury In Vivo Mediate Bladder Smooth Muscle Cell Growth In Vitro

No AccessJournal of UrologyINVESTIGATIVE UROLOGY1 Feb 2003Integrins Expressed With Bladder Extracellular Matrix After Stretch Injury In Vivo Mediate Bladder Smooth Muscle Cell Growth In Vitro JYOTI UPADHYAY, KAREN J. AITKEN, CHRISTOPHER DAMDAR, STEPHANE BOLDUC, and DARIUS J. BÄGLI JYOTI UPADHYAYJYOTI UPADHYAY More articles by this author , KAREN J. AITKENKAREN J. AITKEN More articles by this author , CHRISTOPHER DAMDARCHRISTOPHER DAMDAR More articles by this author , STEPHANE BOLDUCSTEPHANE BOLDUC More articles by this author , and DARIUS J. BÄGLIDARIUS J. BÄGLI More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)64007-4AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: It is unknown how bladder smooth muscle cells sense extrinsic mechanical stimuli. The integrins are a large versatile family of transmembrane mechanoreceptors that transduce extracellular matrix (ECM) alterations into the cell, thereby, regulating proliferation, differentiation and ECM synthesis. To our knowledge we provide the first evidence that the integrins may be involved in responses to whole bladder distention and bladder smooth muscle cell stretch. Materials and Methods: Bladders from 100 to 120 gm. rats were stretched to 40 cm. H2O for 5 minutes. Five to 96 hours after distention whole bladder mRNAs were isolated for analysis of temporal expression of collagen and integrin genes. Separately quiescent primary culture bladder smooth muscle cells from 1-day-old Sprague-Dawley rats were stretched cyclically for 4 hours. Relative expression of select integrin subunit mRNAs was assessed by semiquantitative reverse transcriptase-polymerase chain reaction. Integrin blockade with asparagine-glycine-arginine peptides was used to determine the role of integrins in stretch induced proliferation and the cell cycle in bladder smooth muscle cells. Results: Within 24 hours bladder distention stimulated collagen expression 2-fold (type I) and 5-fold (type III). Collagen levels beyond 24 hours were 8-fold (type I) and 2-fold (type III) greater than in controls, revealing an inverse temporal type I-to-III ratio beyond 24 hours. Coordinate alterations were observed in integrin and collagen expression. In vitro bladder smooth muscle cell integrin β1, β3 and αv subunit expression was increased by mechanical stretch 2.5, 3.8 and 5-fold, respectively, while α1 expression decreased. Asparagine-glycine-arginine peptide inhibition of integrin function significantly inhibited stretch induced bladder smooth muscle cell proliferation and exit from the G2/M phase of the cell cycle. Conclusions: To our knowledge these results demonstrate for the first time that that bladder distention initiates dynamic alterations in ECM expression. The ability of integrin blockade to suppress stretch induced bladder smooth muscle cell proliferation and the coordinate changes in bladder ECM and integrin expression suggest that integrins mediate key responses to mechanical stimuli in the bladder. Furthermore, cell cycle analysis of resting and stretched bladder smooth muscle cells revealed novel avenues for the examination of integrin and stretch regulation of bladder smooth muscle cell growth. References 1 : Differences in bladder compliance with time and associations of bladder management with compliance in spinal cord injured patients. J Urol2000; 163: 1228. Link, Google Scholar 2 : Collagen types I and III localization by in situ hybridization and immunohistochemistry in the partially obstructed young rabbit bladder. J Urol1996; 156: 582. part 2. Link, Google Scholar 3 : Effect of physical forces on bladder smooth muscle and urothelium. J Urol1993; 150: 601. part 2. Link, Google Scholar 4 : Cell adhesion molecules: selectins and integrins. Crit Rev Immunol1999; 19: 389. Google Scholar 5 : Relevance of extracellular matrix, its receptors, and cell adhesion molecules in mammalian nephrogenesis. Am J Physiol, part 21998; 275: F467. Google Scholar 6 : Insulin induces epidermal growth factor (EGF) receptor clustering and potentiates EGF-stimulated DNA synthesis in swiss 3T3 cells: a mechanism for costimulation in mitogenic synergy. Immunol Cell Biol2000; 78: 408. Google Scholar 7 : Integrins: versatility, modulation, and signaling in cell adhesion. Cell1992; 69: 11. Google Scholar 8 : The hyaluronic acid receptor is induced by stretch injury of rat bladder in vivo and influences smooth muscle cell contraction in vitro. J Urol1999; 162: 832. Link, Google Scholar 9 : Extracellular matrix gene responses in a novel ex vivo model of bladder stretch injury. J Urol2001; 165: 2235. part 2. Link, Google Scholar 10 : Heparin inhibits proliferation of myometrial and leiomyomal smooth muscle cells through the induction of alpha-smooth muscle actin, calponin h1 and p27. Mol Hum Reprod1999; 5: 139. Google Scholar 11 : Extracellular matrix and integrin composition of the normal bladder wall. World J Urol1996; 14: S30. Crossref, Medline, Google Scholar 12 : Molecular analysis of collagens in bladder fibrosis. J Urol1998; 160: 1518. Link, Google Scholar 13 : Direct stimulation of bladder smooth muscle cell (SMC) growth by altered extracellular matrix (ECM) in vitro is regulated by MAP kinase (MAPK). J Urol2001; 165: 86. abstract 352. Google Scholar 14 : Human smooth muscle VLA-1 integrin: purification, substrate specificity, localization in aorta, and expression during development. J Cell Biol1990; 111: 2159. Google Scholar 15 : Differential expression of beta 1 integrins in nonneoplastic smooth and striated muscle cells and in tumors derived from these cells. Am J Pathol1994; 144: 1172. Google Scholar 16 : Integrin activation: the link between ligand binding and signal transduction. Curr Opin Cell Biol1996; 8: 632. Google Scholar 17 : RGD and other recognition sequences for integrins. Annu Rev Cell Dev Biol1996; 12: 697. Google Scholar 18 : Affinity of integrins for damaged extracellular matrix: alpha v beta 3 binds to denatured collagen type I through RGD sites. Biochem Biophys Res Commun1992; 182: 1025. Google Scholar 19 : Inhibition of integrin function by a cyclic RGD-containing peptide prevents neointima formation. Circulation1994; 90: 2203. Google Scholar 20 : Physiological cyclic stretch causes cell cycle arrest in cultured vascular smooth muscle cells. Am J Physiol Heart Circ Physiol2000; 278: H748. Google Scholar 21 : Comparison of the effects of mechanical stimulation on venous and arterial smooth muscle cells in vitro. J Vasc Res1996; 33: 405. Google Scholar 22 : Calcium antagonists differently inhibit proliferation of human coronary smooth muscle cells in response to pulsatile stretch and platelet-derived growth factor. Circulation1993; 88: 832. Google Scholar 23 : Expression of cyclins and cyclin-dependent kinases in smooth muscle tumors of the uterus. Int J Cancer1999; 84: 244. Google Scholar 24 : Intimal hyperplasia after vascular injury is inhibited by antisense cdk 2 kinase oligonucleotides. J Clin Invest1994; 93: 1458. Google Scholar From the Infection, Immunity, Injury and Repair Division, Hospital for Sick Children Research Institute and Division of Urology, University of Toronto, Toronto, Ontario, Canada© 2003 by American Urological Association, Inc.FiguresReferencesRelatedDetailsCited byLuo D, Wazir R, Tian Y, Yue X, Wei T and Wang K (2013) Integrin αv Mediates Contractility Whereas Integrin α4 Regulates Proliferation of Human Bladder Smooth Muscle Cells via FAK Pathway under Physiological StretchJournal of Urology, VOL. 190, NO. 4, (1421-1429), Online publication date: 1-Oct-2013.Parekh A, Long R, Chancellor M and Sacks M (2009) Assessing the Effects of Transforming Growth Factor-β1 on Bladder Smooth Muscle Cell Phenotype. II. Modulation of Collagen OrganizationJournal of Urology, VOL. 182, NO. 3, (1216-1221), Online publication date: 1-Sep-2009. Volume 169Issue 2February 2003Page: 750-755 Advertisement Copyright & Permissions© 2003 by American Urological Association, Inc.Keywordsbladderintegrinsrats, Sprague-Dawleymuscle, smoothextracellular matrixMetricsAuthor Information JYOTI UPADHYAY More articles by this author KAREN J. AITKEN More articles by this author CHRISTOPHER DAMDAR More articles by this author STEPHANE BOLDUC More articles by this author DARIUS J. BÄGLI More articles by this author Expand All Advertisement PDF downloadLoading ...