TLR4 and brain inflammatory disease: While brain inflammation is associated with enhanced reactive astrocytes and recruitment of peripheral macrophages (Ransohoff and Brown, 2012), microglia are considered as the main target of LPS as these glial cells specifically express of TLR4 (Lehnardt et al., 2002, 2003; reviewed in Lehnardt, 2010), are rapidly activated during the acute phase of the central nervous system before the recruitment of peripheral macrophages (Greenhalgh and David, 2014) and forms the main source of inflammatory cytokines such as TNF-α and IL-6 (Lee et al., 1993; Lafortune et al., 1996; Hanisch, 2002).