Calcium (Ca2+) signalling disturbances in lens epithelial cells (LECs) are one of the key factors involved in cataract formation. We decided to explore and identify intercellular Ca2+ signalization in human LECs upon local mechanic stimulation, to understand better the role of intercellular communication and its connection to cataractogenesis and posterior capsule opacification (PCO) development as well as lens regeneration. We used fresh postoperative lens capsules (LCs) obtained during cataract surgery. We mechanically stimulated anterior LECs with glass micropipette, which induced an increase in intracellular Ca2+ concentration ([Ca2+]i). By following the spatio-temporal changes in [Ca2+]i we discovered that Ca2+ signal spreads radially from stimulation point and that the amplitude of Ca2+ transients decreases with increasing distance from stimulation. When we analysed signalling characteristics with respect to degree of cataract progression, we discovered that in LCs from more developed cataracts the Ca2+ wave propagates faster, the amplitudes of Ca2+ signals are lower, whereas their durations are longer. On contrary, no significant differences were observed when comparing LCs with regard to the type of the cataract. From this we can conclude that cataractogenesis is associated with changes in intracellular signalization of Ca2+, as well as with changes in intercellular communication. Moreover, we grew ex vivo cultures of the LC explants to follow functional properties of LECs, which are important for studying PCO and lens regeneration. With local mechanical stimulation we showed responding of grown LECs, which can be in future used for testing of different physical and pharmacological agents.
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