title: In Vitro Inhibition of NFAT5-Mediated Induction of CCL2 in Hyperosmotic Conditions by Cyclosporine and Dexamethasone on Human HeLa-Modified Conjunctiva-Derived Cells.
abstract: OBJECTIVE
  To investigate the pro-inflammatory intracellular mechanisms induced by an in vitro model of dry eye disease (DED) on a Hela-modified conjunctiva-derived cells in hyperosmolarity (HO) stress conditions. This study focused on CCL2 induction and explored the implications of the nuclear factor of activated T-cells 5 (NFAT5) as well as mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NFĸB). This work was completed by an analysis of the effects of cyclosporine A (CsA), dexamethasone (Dex) and doxycycline (Dox) on HO-induced CCL2 and NFAT5 induction.
  
  
  METHODS
  A human HeLa-modified conjunctiva-derived cell line was cultured in NaCl-hyperosmolar medium for various exposure times. Cellular viability, CCL2 secretion, NFAT5 and CCL2 gene expression, and intracytoplasmic NFAT5 were assessed using the Cell Titer Blue® assay, enzyme-linked immunosorbent assay (ELISA), RT-qPCR and immunostaining, respectively. In selected experiments, inhibitors of MAPKs or NFκB, therapeutic agents or NFAT5 siRNAs were added before the hyperosmolar stimulations.
  
  
  RESULTS
  HO induced CCL2 secretion and expression as well as NFAT5 gene expression and translocation. Adding NFAT5-siRNA before hyperosmolar stimulation led to a complete inhibition of CCL2 induction and to a decrease in cellular viability. p38 MAPK (p38), c-Jun NH2-terminal kinase (JNK) and NFĸB inhibitors, CsA and Dex induced a partial inhibition of HO-induced CCL2, while Dox and extracellular signal-regulated kinase (ERK) inhibitor did not. Dex also induced a partial inhibition of HO-induced NFAT5 gene expression but not CsA or Dox.
  
  
  CONCLUSIONS
  These in vitro results suggest a potential role of CCL2 in DED and highlight the crucial role of NFAT5 in the pro-inflammatory effect of HO on HeLa-modified conjunctiva-derived cells, a rarely studied cellular type. This inflammatory pathway involving NFAT5 and CCL2 could offer a promising target for developing new therapies to treat DED, warranting further investigations to fully grasp the complete intracellular mechanisms.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris, France.|CHNO des Quinze-Vingts, Service Pharmacie, Paris, France.
authors.forename: Elise
authors.identifier: http://orcid.org/0000-0002-5521-4650
authors.initials: E
authors.lastname: Warcoin
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris, France.|CHNO des Quinze-Vingts, Service III, Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Baudouin
authors.affiliation: Horus Pharma, Saint-Laurent du Var, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Gard
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris, France.|Faculté de Pharmacie de Paris, Univ Paris Descartes, Sorbonne Paris Cité, Paris, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Brignole-Baudouin
mesh_terms: D002460:Cell Line; D018932:Chemokine CCL2 / Q000235:genetics* / Q000378:metabolism; D003228:Conjunctiva / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016572:Cyclosporine / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D009997:Osmotic Pressure / Q000502:physiology*; D021381:Protein Transport / Q000187:drug effects / Q000235:genetics; D014157:Transcription Factors / Q000502:physiology*
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; C118125:NFAT5 protein, human; D014157:Transcription Factors; D003907:Dexamethasone; D016572:Cyclosporine