title: Human keratinocytes respond to direct current stimulation by increasing intracellular calcium: preferential response of poorly differentiated cells.
abstract: A direct current (DC) endogenous electric field (EF) is induced in the wound following skin injury. It is potentially implicated in the wound healing process by attracting cells and altering their phenotypes as indicated by the response to an EF of keratinocytes cultured as individual cells. To better define the signalization induced by a direct current electric field (DCEF) in human keratinocytes, we took advantage of an in vitro model more representative of the in vivo situation since it promotes cell-cell interactions and stratification. Human keratinocytes were grown into colonies. Their exposure to a DCEF of physiological intensity induced an increase of intracellular calcium. This variation of intracellular calcium resulted from an extracellular calcium influx and was mediated, at least in part, by the L-type voltage-gated calcium channel. The increase in intracellular calcium in response to a DCEF was however not observed in all the cells composing the colonies. The intracellular calcium increase was only detected in keratinocytes that didn't express involucrin, a marker of differentiated cells. These results indicate that DCEF is able to induce a specific calcium response in poorly differentiated keratinocytes. This study brings a new perspective for the understanding of the signaling mechanism of endogenous EF in reepithelialization, a critical process during skin wound healing.
authors: Centre LOEX de L'Université Laval, Génie Tissulaire et Régénération: LOEX, Faculté de Médecine, Département de Chirurgie, Université Laval, Québec, QC, Canada.
authors: Jean
authors: J
authors: Dubé
authors: Olivier
authors: O
authors: Rochette-Drouin
authors: Philippe
authors: P
authors: Lévesque
authors: Robert
authors: R
authors: Gauvin
authors: Charles J
authors: CJ
authors: Roberge
authors: François A
authors: FA
authors: Auger
authors: Daniel
authors: D
authors: Goulet
authors: Michel
authors: M
authors: Bourdages
authors: Michel
authors: M
authors: Plante
authors: Véronique J
authors: VJ
authors: Moulin
authors: Lucie
authors: L
authors: Germain
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020746:Calcium Channels, L-Type / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D004558:Electric Stimulation; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011498:Protein Precursors / Q000378:metabolism; D015398:Signal Transduction; D013997:Time Factors; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors / Q000378:metabolism; D014945:Wound Healing / Q000187:drug effects
chemical_list: D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D010726:Phosphodiesterase Inhibitors; D011498:Protein Precursors; C032253:involucrin; D010738:Type C Phospholipases; D002118:Calcium