Chemicals inducing acute irritant contact dermatitis mobilize intracellular calcium in human keratinocytes.
Intracellular Ca(2+) increase is a common feature of multiple cellular pathways associated with receptor and channel activation, mediator secretion and gene regulation. We investigated the possibility of using this Ca(2+) signal as a biomarker for a reaction to chemical irritants of normal human keratinocytes (NHK) in submerged primary cell culture. We tested 14 referenced chemical compounds classified as strong (seven), weak (four) or non- (three) irritants in acute irritant contact dermatitis. We found that the strong irritant compounds tested at 20-40 mM induced an intracellular Ca(2+) increase measurable by spectrofluorimetry in an automated test. Weak and non-irritant compounds however did not increase intracellular Ca(2+) concentration. We further investigated the mechanisms by which the amine heptylamine, classified as a R34 corrosive compound, increases intracellular Ca(2+). Heptylamine (20mM) induced an ATP release that persisted in the absence of intra- and extra-cellular Ca(2+). In addition, we found that this ATP activates NHK purinergic receptors that subsequently cause the increase in intracellular Ca(2+) from sarcoplasmic reticular stores. We conclude that measuring the intracellular Ca(2+) concentration in NHK is a suitable and easy way of determining any potential reaction to soluble chemical compounds.
Université de la Méditerranée, Centre National de la Recherche Scientifique UMR 6231, Marseille, France.
Matthieu
M
Raoux
Nathalie
N
Azorin
Cécile
C
Colomban
Stéphanie
S
Rivoire
Thierry
T
Merrot
Patrick
P
Delmas
Marcel
M
Crest
D000255:Adenosine Triphosphate / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004396:Coloring Agents / Q000378:metabolism; D017453:Dermatitis, Irritant; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007509:Irritants / Q000633:toxicity*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009499:Neutral Red / Q000378:metabolism; D023422:Skin Irritancy Tests
D004396:Coloring Agents; D007509:Irritants; D009499:Neutral Red; D000255:Adenosine Triphosphate; D002118:Calcium