BDNF and systemic lupus erythematosus: 110 pathways were significantly affected by the downregulated genes (p < 0.05) in the hippocampus, including tight junction, gap junction, focal adhesion, systemic lupus erythematosus, regulation of actin cytoskeleton, long-term depression, alcoholism, prostate cancer, neurotrophin signalling pathway, MAPK signalling pathway, estrogen signalling pathway, vascular smooth muscle contraction, viral carcinogenesis, GnRH signalling pathway, leukocyte transendothelial migration(Fig. 3f).