IL6 and Alzheimer disease: Activated microglia contribute to neuronal damage in AD patients and transgenic mice by impairing Aβ clearance and overexpression of inflammatory cytokines (such as IL-1β, IL-6, and TNF-α), resulting in neurodegeneration in the corresponding brain regions.28,29 Our present study showed that microglia also released a large amount of proinflammatory factors while engulfing Aβ and synapses (Fig. 3l).