title: Abscisic acid activates the murine microglial cell line N9 through the second messenger cyclic ADP-ribose.
abstract: Abscisic acid (ABA) is a phytohormone regulating important functions in higher plants, notably responses to abiotic stress. Recently, chemical or physical stimulation of human granulocytes was shown to induce production and release of endogenous ABA, which activates specific cell functions. Here we provide evidence that ABA stimulates several functional activities of the murine microglial cell line N9 (NO and tumor necrosis factor-alpha production, cell migration) through the second messenger cyclic ADP-ribose and an increase of intracellular calcium. ABA production and release occur in N9 cells stimulated with bacterial lipopolysaccharide, phorbol myristate acetate, the chemoattractant peptide f-MLP, or beta-amyloid, the primary plaque component in Alzheimer disease. Finally, ABA priming stimulates N9 cell migration toward beta-amyloid. These results indicate that ABA is a pro-inflammatory hormone inducing autocrine microglial activation, potentially representing a new target for anti-inflammatory therapies aimed at limiting microglia-induced tissue damage in the central nervous system.
authors.affiliation: Department of Experimental Medicine, Section of Biochemistry, and Center of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV/1, 16132 Genova, Italy.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Bodrato
authors.forename: Luisa
authors.initials: L
authors.lastname: Franco
authors.forename: Chiara
authors.initials: C
authors.lastname: Fresia
authors.forename: Lucrezia
authors.initials: L
authors.lastname: Guida
authors.forename: Cesare
authors.initials: C
authors.lastname: Usai
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salis
authors.forename: Iliana
authors.initials: I
authors.lastname: Moreschi
authors.forename: Chiara
authors.initials: C
authors.lastname: Ferraris
authors.forename: Claudia
authors.initials: C
authors.lastname: Verderio
authors.forename: Giovanna
authors.initials: G
authors.lastname: Basile
authors.forename: Santina
authors.initials: S
authors.lastname: Bruzzone
authors.forename: Sonia
authors.initials: S
authors.lastname: Scarfì
authors.forename: Antonio
authors.initials: A
authors.lastname: De Flora
authors.forename: Elena
authors.initials: E
authors.lastname: Zocchi