Affiliations 

  • 1 Universiti Putra Malaysia
MyJurnal

Abstract

Neurodegeneration resulting from pathogen invasion or tissue damage has been associated with
activation of microglia, and exacerbated by the release of neurotoxic mediators such as pro-inflammatory cytokines,
chemokines and reactive oxygen species. Activation of microglia stimulated by lipopolysaccharide is mediated in
part by GSK-3 signaling molecule. Induced IL-10 expression via GSK-3 inhibition is noteworthy since IL-10 has been
remarkably shown to suppress inflammation. Objectives: We aimed to inactivate microglia through inhibition of
GSK-3 signaling and to determine its effects on the production of pro- and anti-inflammatory mediators. Methods:
LPS-stimulated BV-2 cells were treated with a GSK-3 inhibitor (LiCl, NP12, SB216763 or CHIR99021). Inhibition
of GSK-3 was determined by the phosphorylation status of GSK-3β. The effects of GSK-3 inhibition on microglial
inflammatory response were investigated by examining various mediators and CD200R marker. Production of nitric
oxide (NO), glutamate and pro- and anti-inflammatory cytokines were measured using flow cytometry, Griess assay,
glutamate assay and Cytometric Bead Array (CBA) respectively. Results: GSK-3β signaling in LPS-stimulated microglia
was blocked by GSK-3 inhibitor through increased phosphorylation at Serine 9 residue. GSK-3 inhibitors had also
led to reducing in microglia activity via increased expression of CD200R. Inhibition of GSK-3 also diminished
inflammatory mediators such as nitric oxide (NO), glutamate, pro-inflammatory cytokines (TNF-α and IL-6) and
chemokine, MCP-1. Reduction of pro-inflammatory mediators by GSK-3 inhibitor was coincided with increased
IL-10 production. Conclusions: Suppression of microglia-mediated inflammatory response was facilitated by GSK-3
inhibition with associated increased in IL-10 production.