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Spontaneous and mechanically induced Ca 2+ activity changes in hESC ‐ RPE cells during maturation
Author(s) -
Abu Khamidakh A.,
JuutiUusitalo K.,
Caetano dos Santos F.,
Skottman H.,
Hyttinen J.
Publication year - 2015
Publication title -
acta ophthalmologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.534
H-Index - 87
eISSN - 1755-3768
pISSN - 1755-375X
DOI - 10.1111/j.1755-3768.2015.0323
Subject(s) - extracellular , intracellular , gap junction , thapsigargin , microbiology and biotechnology , receptor , chemistry , biophysics , biology , biochemistry
Purpose The aim of this study was to investigate changes in spontaneous Ca 2+ activity and mechanically induced intercellular Ca 2+ communication in human embryonic stem cells‐derived retinal pigment epithelium ( hESC ‐ RPE ) during maturation. Methods In this study, we assessed Ca 2+ activity in hESC ‐ RPE cells cultured for 9 or 28 days. Ca 2+ imaging was done using a Ca 2+ ‐sensitive fluorescence dye fluo‐4‐ AM . Spontaneous Ca 2+ activity and mechanically induced intercellular Ca 2+ communication were recorded in control conditions, in the absence of extracellular Ca 2+ , after depletion of intracellular Ca 2+ stores with thapsigargin, in presence of a gap junction blocker α ‐glycyrrhetinic acid and a P2‐receptor blocker suramin. Results 9 days cells exhibited twice lower spontaneous Ca 2+ activity and 4‐fold higher mechanically induced intercellular Ca 2+ communication compared to 28 days cells. Absence of extracellular Ca 2+ reduced spontaneous Ca 2+ activity in 9 days cells and almost completely inhibited it in 28 days cells, while having no effect on mechanically induced intercellular Ca 2+ communication. Depletion of intracellular Ca 2+ stores abolished spontaneous Ca 2+ activity in 9 days and 28 days cells, as well as mechanically induced intercellular Ca 2+ communication in 28 days cells, while not affecting the latter in 9 days cells. Blockade of gap junctions and P2‐receptors had no effect on spontaneous Ca 2+ activity or mechanically induced intercellular Ca 2+ communication in cells from both time points. Conclusions Our results show that hESC ‐ RPE cells undergo significant Ca 2+ signaling re‐arrangements during maturation: the cells increase spontaneous Ca 2+ activity, while decreasing their intercellular Ca 2+ communication.