There is some evidence linking brain neuroimmune or proinflammatory signaling to alcohol action. Long lasting increases in levels of several cytokines, including MCP-1 (Ccl2) in mouse brain, were found after chronic pretreatment with high doses of ethanol followed by injection of lipopolysaccharide (LPS) (Qin et al., 2008). Interestingly, a similar increase in MCP-1 (Ccl2) was found in the brain of human alcoholics (He and Crews, 2008) and deletion of Ccl2 or its receptor in mice decreased alcohol consumption (Blednov et al., 2005). Recently, Kong et al. (2010) found up-regulation of genes in the Toll and Imd signaling pathways in Drosophila exposed to ethanol, extending the link between alcohol and immune mediators to an invertebrate species.
