RT Journal Article
T1 Hyperosmotic stress induces ATP release and changes in P2X7 receptor levels in human corneal and conjunctival epithelial cells
A1 Guzmán Aránguez, Ana Isabel
A1 Pérez de Lara, María Jesús
A1 Pintor, Jesús
AB Tear hyperosmolarity is a key event in dry eye. In this work, we analyzed whether hyperosmolar challenge induces ATP release on the ocular surface. Moreover, as extracellular ATP can activate P2X7 receptor, the changes in P2X7 protein levels and its involvement in pathological process triggered by hypertonic treatment were also examined. High-performance liquid chromatography analysis revealed that ATP levels significantly increased in human corneal and conjunctival epithelial cells exposed to hyperosmotic challenge as well as in dry eye patients as compared to control subjects. A significant reduction in cell viability was detected after hyperosmolar treatment, indicating that the rise in ATP release was mainly due to cell lysis/death. Additionally, vesicular nucleotide transporter was identified in both cell lines and their protein expression was upregulated in hypertonic media. P2X7 receptor truncated form together with the full-length form was identified in both cell lines, and experiments using specific antagonist and agonist for P2X7 indicated that this receptor did not mediate cell death induced by hyperosmolar stress. In conclusion, hyperosmotic stress induces ATP release. Extracellular ATP can activate P2X7 receptor leading to cytotoxicity in many cells/tissues; however, this does not occur in human corneal and conjunctival epithelial cells. In these cells, the presence of P2X7 receptor truncated form together with the full-length form hinders a P2X7 apoptotic behavior on the ocular surface.
PB Springer
SN 1573-9538
YR 2017
FD 2017-06
LK https://hdl.handle.net/20.500.14352/17853
UL https://hdl.handle.net/20.500.14352/17853
LA eng
NO Received: 2 November 2016 /Accepted: 25 January 2017 /Published online: 7 February 2017
NO Ministerio de Economía y Competitividad (MINECO)
NO Instituto Carlos III (RETICS)
DS Docta Complutense
RD 2 may 2024