title: Human mesenchymal stem cell responses to hydrostatic pressure and shear stress.
abstract: The effects of mechanical stimuli to which cells are exposed in vivo are, at best, incompletely understood; in this respect, gene-level information regarding cell functions which are pertinent to new tissue formation is of special interest and importance in applications such as tissue engineering and tissue regeneration. Motivated by this need, the present study investigated the early responses of human mesenchymal stem cells (hMSCs) to intermittent shear stress (ISS) and to cyclic hydrostatic pressure (CHP) simulating some aspects of the biological milieu in which these cells exist in vivo. Production of nitric oxide (NO) and mRNA expression of several known mechanosensitive genes as well as ERK1/2 activation in the hMSC response to the two mechanical stimuli tested were monitored and compared. NO production depended on the type of the mechanical stimulus to which the hMSCs were exposed and was significantly higher after exposure to ISS than to CHP. At the conditions of NO peak release (i.e., at 0.7 Pa for ISS and 50,000 Pa for CHP), ISS was more effective than CHP in up-regulating mechanosensitive genes. ERK1/2 was activated by ISS but not by CHP. The present study is the first to report that PGTS2, IER3, EGR1, IGF1, IGFBP1, ITGB1, VEGFA and FGF2 are involved in the response of hMSCs to ISS. These findings establish that, of the two mechanical stimuli tested, ISS is more effective than CHP in triggering expression of genes from hMSCs which are bioactive and pertinent to several cell functions (such as cell differentiation and release of specific growth factors and cytokines) and also to tissue-related processes such as wound healing.
authors.affiliation: Laboratory of Bioengineering and Bioimaging for Bone Articulation (B2OA, UMR CNRS 7052), University of Paris 7, PRES Paris Cité, 10 Avenue de Verdun, 75010 Paris, France.morad.bensidhoum@univ-paris-diderot.fr.
authors.forename: P
authors.initials: P
authors.lastname: Becquart
authors.forename: M
authors.initials: M
authors.lastname: Cruel
authors.forename: T
authors.initials: T
authors.lastname: Hoc
authors.forename: L
authors.initials: L
authors.lastname: Sudre
authors.forename: K
authors.initials: K
authors.lastname: Pernelle
authors.forename: R
authors.initials: R
authors.lastname: Bizios
authors.forename: D
authors.initials: D
authors.lastname: Logeart-Avramoglou
authors.forename: H
authors.initials: H
authors.lastname: Petite
authors.forename: M
authors.initials: M
authors.lastname: Bensidhoum
mesh_terms: D001854:Bone Marrow Cells / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D006874:Hydrostatic Pressure / Q000009:adverse effects*; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D009569:Nitric Oxide / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D013314:Stress, Mechanical; D013312:Stress, Physiological / Q000502:physiology*; D023822:Tissue Engineering / Q000379:methods
chemical_list: D012333:RNA, Messenger; D009569:Nitric Oxide; D048049:Extracellular Signal-Regulated MAP Kinases