201 BLADDER STRAIN INDUCED MICROENVIRONMENT ATTENUATES SMOOTH MUSCLE DIFFERENTIATION OF ADULT RAT SKIN DERIVED PRECURSOR CELLS: IMPLICATIONS FOR TISSUE REGENERATION/ENGINEERING

Abstract

You have accessJournal of UrologyStem Cell Research1 Apr 2012201 BLADDER STRAIN INDUCED MICROENVIRONMENT ATTENUATES SMOOTH MUSCLE DIFFERENTIATION OF ADULT RAT SKIN DERIVED PRECURSOR CELLS: IMPLICATIONS FOR TISSUE REGENERATION/ENGINEERING Cornelia Tolg, Shaalee Dworski, Karen Aitken, Jeff Biernaskie, and Darius Bagli Cornelia TolgCornelia Tolg Toronto, Canada More articles by this author , Shaalee DworskiShaalee Dworski Toronto, Canada More articles by this author , Karen AitkenKaren Aitken Toronto, Canada More articles by this author , Jeff BiernaskieJeff Biernaskie Toronto, Canada More articles by this author , and Darius BagliDarius Bagli Toronto, Canada More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.254AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Smooth muscle cell containing organs such as bladder, heart and blood vessels are targeted by a variety of pathological conditions necessitating surgery or organ replacement. Currently, tissue engineering approaches are hampered by lack of functional smooth muscle cells. Multipotent Skin derived progenitor cells (SKPs) can easily be isolated from adult skin and can be differentiated into a variety of cell lineages. Here we describe the opposing effects of FBS and the bladder microenvironment on induction of smooth muscle cell differentiation in SKPs. METHODS SKPs isolated from adult rats were cultured in medium containing either EGF/FGF or FBS. Expression of smooth muscle cell marker was analyzed by qPCR and immunofluorescent staining followed by confocal microscopy. RESULTS SKPs cultured in presence of FBS strongly upregulate expression of smooth muscle marker such as smooth muscle actin, calponin, myocardin and myosin heavy chain compared to SKPs cultured in EGF/FGF containing medium as demonstrated by real time PCR and IF. FBS treated SKPs organize smooth muscle actin into cytoskeleton actin cables and contract collagen I gels, two characteristics of functional smooth muscle cells (SMC). In vivo, bladder strain induces microenvironmental changes lead to de-differentiation of fully differentiated bladder SMC. To investigate how this strain induced bladder microenvironment modifies SMC differentiation of SKPs, we differentiated SKPs in presence of bladder organoids or conditioned medium derived from stretched or relaxed bladders. Diffusible factors released from stretched bladders decreased SMC differentiation of SKPs. Inhibition of mTOR signalling using Rapamycin treatment, previously observed to prevent dedifferentiation of fully differentiated bladder SMC in vitro, revealed here that FBS induced SMC differentiation of SKPs requires mTOR signaling. CONCLUSIONS These results suggest that SKPs could be used as a source for SMCs in regenerative strategies for hollow organs such as the bladder. However, it is also apparent that organ-specific microenvironmental contexts play a significant role in modulating or even inhibiting stem cell phenotypic changes, possibly explaining the variable or less than exuberant differentiation of stem cell constructs in in vivo settings. These observations must be considered in drafting any overall regeneration strategies. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e84 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Cornelia Tolg Toronto, Canada More articles by this author Shaalee Dworski Toronto, Canada More articles by this author Karen Aitken Toronto, Canada More articles by this author Jeff Biernaskie Toronto, Canada More articles by this author Darius Bagli Toronto, Canada More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...