Lipoxin A4 activates ALX/FPR2 receptor to regulate conjunctival goblet cell secretion.

Related Articles

Lipoxin A4 activates ALX/FPR2 receptor to regulate conjunctival goblet cell secretion.

Mucosal Immunol. 2017 Jan;10(1):46-57

Authors: Hodges RR, Li D, Shatos MA, Bair JA, Lippestad M, Serhan CN, Dartt DA

Abstract
Conjunctival goblet cells play a major role in maintaining the mucus layer of the tear film under physiological conditions as well as in inflammatory diseases like dry eye and allergic conjunctivitis. Resolution of inflammation is mediated by proresolution agonists such as lipoxin A4 (LXA4) that can also function under physiological conditions. The purpose of this study was to determine the actions of LXA4 on cultured rat conjunctival goblet cell mucin secretion, intracellular [Ca(2+)] ([Ca(2+)]i), and identify signaling pathways activated by LXA4. ALX/FPR2 (formyl peptide receptor2) was localized to goblet cells in rat conjunctiva and in cultured goblet cells. LXA4 significantly increased mucin secretion, [Ca(2+)]i, and extracellular regulated kinase 1/2 (ERK 1/2) activation. These functions were inhibited by ALX/FPR2 inhibitors. Stable analogs of LXA4 increased [Ca(2+)]i to the same extent as LXA4. Sequential addition of either LXA4 or resolvin D1 followed by the second compound decreased [Ca(2+)]i of the second compound compared with its initial response. LXA4 activated phospholipases C, D, and A2 and downstream molecules protein kinase C, ERK 1/2, and Ca(2+)/calmodulin-dependent kinase to increase mucin secretion and [Ca(2+)]i. We conclude that conjunctival goblet cells respond to LXA4 to maintain the homeostasis of the ocular surface and could be a novel treatment for dry eye diseases.

PMID: 27072607 [PubMed - indexed for MEDLINE]

from #ENT-PubMed via ola Kala on Inoreader http://ift.tt/2gGf8Sm