Scavenger receptor class A ligands induce secretion of IL1β and exert a modulatory effect on the inflammatory activation of astrocytes in culture

Class-A scavenger receptor (SR-A) is expressed by microglia, and we show here that it is also expressed by astrocytes, where it participates on their inflammatory activation. Astrocytes play a key role on the inflammatory response of the central nervous system, secreting several soluble mediators like cytokines and radical species. Exposure to SR ligands activated MAPKs and NF-kappa B signaling and increased production of IL1 beta and nitric oxide (NO). IL1 beta classically an inflammatory cytokine surprisingly did not increase but inhibited LPS + IFN gamma-induced NO production by astrocytes. Our results suggest that SRs expressed by astrocytes participate in the modulation of inflammatory activation. (C) 2012 Elsevier B.V. All rights reserved.