Pre- and Early Post-treatment With Arthrospira platensis (Spirulina) Extract Impedes Lipopolysaccharide-triggered Neuroinflammation in Microglia

Abstract

<b>Background:</b> Uncontrolled neuroinflammation and microglia activation lead to cellular and tissue damage contributing to neurodegenerative and neurological disorders. Spirulina (<i>Arthrospira platensis</i> (Nordstedt) Gomont, or <i>Spirulina platensis</i>), a blue-green microalga, which belongs to the class of cyanobacteria, has been studied for its numerous health benefits, which include anti-inflammatory properties, among others. Furthermore, <i>in vivo</i> studies have highlighted neuroprotective effects of Spirulina from neuroinflammatory insults in different brain areas. However, the mechanisms underlying the anti-inflammatory effect of the microalga are not completely understood. In this study we examined the effect of pre- and post-treatment with an acetone extract of Spirulina (E1) in an <i>in vitro</i> model of LPS-induced microglia activation. <b>Methods:</b> The effect of E1 on the release of IL-1β and TNF-α, expression of iNOS, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1), and the activation of NF-κB was investigated in primary microglia by ELISA, real-time PCR, and immunofluorescence. <b>Results:</b> Pre- and early post-treatment with non-cytotoxic concentrations of E1 down-regulated the release of IL-1β and TNF-α, and the over-expression of iNOS induced by LPS. E1 also significantly blocked the LPS-induced nuclear translocation of NF-κB p65 subunit, and upregulated gene and protein levels of Nrf2, as well as gene expression of HO-1. <b>Conclusions:</b> These results indicate that the extract of Spirulina can be useful in the control of microglia activation and neuroinflammatory processes. This evidence can support future <i>in vivo</i> studies to test pre- and post-treatment effects of the acetone extract from Spirulina.