Fig. 5

Neuron-derived CCL2 induced the expression of M1 markers in microglia. As mentioned above, the medium and lysates (CM) of neurons stimulated with TNF-α were collected and added into microglia cultures. The microglia was pretreated with 5 μM CCL2 receptor inhibitor (INCB or C021) for 1 h before the addition of CM to block CCL2. After incubation for 24 h, the mRNA expression of iNOS, COX2, Arg-1 and YM-1 in microglia was determined using qRT-PCR (a, b), and the release of IL-6, IL-1, IL-1β, IL-4 and IL-10 were determined using Elisa assay (c, d). **P < 0.01, *P < 0.05, vs Ctrl; ^## P < 0.01, ^# P < 0.05, vs CM