CX3CR1 and Alzheimer disease: To investigate the downstream effects of CREB1 in AD post‐PQQ administration, we performed a real‐time PCR assay based on RNA‐seq results, confirming the upregulation of cannabinoid receptor 1 (Cnr1) and CX3C chemokine receptor 1 (Cx3cr1) expression by PQQ (Figure 9a,b).